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Prehistoric Stone Structures in Saudi Arabia

Date de soumission : 23/01/2023
Critères: (i)(ii)(iii)(iv)
Catégorie : Culturel
Soumis par :
Permanent Delegation of Saudi Arabia to UNESCO
État, province ou région :
Al-Jawf, Tabuk, Madinah, Hail, Makkah, Riyadh
Ref.: 6636

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Les noms des biens figurent dans la langue dans laquelle les États parties les ont soumis.


Name of the Component



Rajajil standing stones




Harrat Khaybar




Harrat Rahat (Madinah Region)




Harrat Kishb




Harrat Lunayyir




Rohab (Tabuk region)




Ha’it oasis




Harrat Nawasif early kites








Al-Faw, piedmont of Jabal Tuwaiq



Previously misunderstood as a perpetual desert landscape unfavourable to human development, the role of the Arabian Peninsula in the origin of human history is being progressively unveiled.

The first humans left Africa to Arabia around 1.7 million years ago, and the first human communities of the peninsula date from the Lower Palaeolithic, which lasted in Arabia until ca. 200,000 years ago. This period characteristically witnessed the production of the Acheulean lithic industry, with large bifacial artefacts (hand-axes and cleavers) as well as simpler tools (choppers). The Middle Palaeolithic, between 125,000 and 55,000 years ago, has left more remains in Arabia, most of which are dated. The episodic peopling of Arabia during the Middle Palaeolithic is associated with well-established humid phases in which increased rainfall facilitated the expansion of both freshwater systems and mammals’ population. On the contrary, the Upper Palaeolithic, characterized by the development of blade tool industries in the Levant and Europe, seems almost unrepresented in the Arabian Peninsula. The absence of blade industries in Arabia, however, might also be due to poor preservation conditions, or result from a lack of research.

Human presence in the Peninsula seems to thrive again from the beginning of the “Arabian Humid Period” in the Early Holocene, 10,000 to 12,000 years ago, when new stone tools, like projectile weapons and arrowheads, were created, paving the way to the Neolithization process. From the mid-7th millennium BCE, Arabia witnessed the progressive rise of pastoralism, the domestication of donkeys for transportation, and the emergence of unprecedented artistic practices (rock art). The Chalcolithic period describes the transition period induced by the “Neolithic revolution” which led to the Bronze Age, beginning around the 4th millennium BCE, with the first civilizations developing in Mesopotamia and in the Peninsula (around oases such as Qurayyah, Tayma and Dilmun). The later Early Iron Age, dated between 1300 and 300 BCE, coincides in Arabia with the domestication of camels and the emergence of ancient kingdoms along the frankincense caravan road, further strengthened during the Late Iron Age, from 300 BCE to 300 CE.

The date of the stone structures that dot most of the Arabian Peninsula is still subject to debate, and it is likely that they span over a long period. The oldest among them might date already to the 7th - 6th millennium BCE, while more elaborated elements, such as cairns, tentatively date from the 1st millennium BCE, but their analysis and scientific study is still at an early stage. Indeed, while the discovery of these monumental structures by the scientific community is recent, they were collectively known locally by the Bedouin communities as “the Work of the Old Men” (rajajil). The importance of prehistoric communities in Arabia began to be acknowledged only in the 1950s, when the first plane flights provided good quality aerial images of the Kingdom.

Research in this field is still in its infancy, but the stone structures of Arabia stand out for their incredibly high number - a preliminary rough estimate indicates approximately 1 million of them - their geographic distribution all over the Peninsula, and their diversity of design, meaning/use, and epochs, that sometime spanned several millennia through maintenance and/or reuse. Stone structures tend to be concentrated in specific remote and desert areas, where they form dense and coherent clusters, notably in volcanic fields, but their geographic distribution shows a cultural homogeneity across the entire peninsula.

Stone structures preserved until today are commonly clustered on valley’s foothills. Depending on their typology, they also tend to be found within specific geological contexts, either lying into volcanic fields or in the vicinity of wadis. They reflect the human communities’ impact in shaping their surrounding environment, before and in parallel with the Neolithic transition process, that entailed major technical and economical innovations including the development of agriculture, animal domestication and development of shepherd lifestyle, the creation of the first settled villages, and ceramic development.

The serial property of the Prehistoric Stone Structures in Saudi Arabia represents a selection of the most outstanding examples known to date, of this still largely unresearched heritage. While future studies and archaeological research might lead to a finetuning of the elements composing the series, the 10 proposed areas form a coherent corpus that ensures the complete representation of the features and processes conveying its significance. Their outstanding relevance relates either to their extraordinary dimensions (reaching several hundreds of meters) or to the density of assets forming coherent ensembles in a limited area.

The Prehistoric Stone Structures in Saudi Arabia include a full range of typologies, likely related to different periods, to reflect the diversity of the extraordinary legacy of the “Work of the Old Men”. Below are briefly outlined the most common typologies of “stone structures” found in the Peninsula.

Megalithic Sites: Megalithic sites are spread throughout the Arabian Peninsula from Jordan to Yemen. Within the Kingdom of Saudi Arabia, they are mostly found in North-West Arabia, and in the regions of Riyadh and Qassim. In total, 16 “henges” were identified in the kingdom, often forming stones circles of different size.

Mustatil: Meaning “rectangle” in Arabic, this stone structure typology is found only in the North-West of Arabia, particularly in the vicinity of the oases of Al Ula and Khaybar. Usually clustered in groups, they resemble fallen barred gates on aerial views. The longest known mustatil is over 500m-long, but most are much smaller. Their date of construction ranges between the 6th and the 3rd millennium BCE. Built of locally available stones, these complex rectangular structures are composed of a base (sometimes with an entranceway), long walls — built of two faces of cut or natural stones filled with rubble — a courtyard, and a “head” at the top, forming a platform sometimes endowed with niches. Some of these niches hiding faunal remains have been dated to the 6th millennium BCE, and suggest a ritual use associated to a cattle cult. Cattle were a vital commodity for the early pastoral inhabitants of Arabia, and their importance for human communities is highlighted by the Arabian rock art that often depicts scenes of cattle herding and hunting.

Kites: Desert “kites” are km-long stone wall constructions, consisting of two or more widely gaping guiding walls that converge to an opening (gate) behind a small sill. Behind is a walled enclosure. In the early stages, these enclosures were bag-like, later clover-like, and in the latest development they developed into very large star-shaped plans. At the apexes of the inward curved enclosure walls, “blinds” — 3 to 5m wide stone circles — were erected. Some kites have a dozen or more of such circles that are generally interpreted as animal traps: once the prey jumped into them, they could not leave them anymore (lacking forward speed) becoming easy prey for the hunters. Harrat Khaybar presents a strong concentration of kites (approx. 917 kites were identified in a 2014 survey), although they are also found in other regions (notably in Harrat Kishb south of Madinah). Kites are found also across the larger region in Jordan, Syria, Turkey, and the Sinai. The oldest known examples date from the 7th up to 9th millennia BCE. They present multiple shapes, ranging from Y-shaped, to star-shaped, to barbed kites — the latter being exclusive to Khaybar. They do not only constitute an extraordinarily innovative hunting technique, but likely also paved the way to animal breeding. For their size and scope, they also bear witness of a certain territoriality, if not a long-term control over the territory where they were built.

Circular stone structures: Multiple circular stone structures, belonging to different typologies, are found across the entire territory of the Kingdom of Saudi Arabia and beyond (notably in Jordan and Syria, where stone circles are dated to the Middle East’s Neolithic period — 8500 BCE to 4300 BCE). The Hejaz and Hisma regions are particularly rich of such structures. They present different designs and sizes. Some of them have a diameter ranging from 20 to 50 meters. Their scope and use are still debated. Some specimens are interpreted as circular burials while others as suggested by the presence of a central chamber in their middle, of much smaller diameter, have been identified as agglomerations of houses, as the stone circles are sometimes imbricated into each other.

Cairns: Cairns are heaped or constructed piles of stones, usually attributed to the Bronze Age. Their function can vary, but larger structures are associated with burials. Their design is extraordinarily rich and varied. “Ring cairns” have an outer ring made of large basalt boulders with a square, rectangular, or circular burial chamber in the middle. The area between the burial chamber and the outer ring is entirely filled in with stones of all sizes, giving these cairns a conical appearance. Another common type of burial is the “round tower tomb”, up to 5 m in diameter and 1.5 m high. This type differs from other cairns by their distinct tower-like shape and their slightly tapering facade made of large, undressed blocks. Visibility seems to have been an obvious target of their builders.

Pendant structures: ranging from round “bulls-eye” and triangular tailed structures to dotted alignment and “keyholes”, they display an impressive diversity of geometrical forms deployed over tens, or hundreds, of meters.

The Prehistoric Stone Structures in Saudi Arabia serial property is composed of a selection of clusters and sites representing major examples of each known typology and epoch of stone structures. Below, each cluster (component of the series) is briefly presented.

Rajajil Standing Stones

The “Rajajil” site, located 20-km south of Sakakah in Al-Jawf region, is the best preserved and the most complex example of the Saudi henge corpus. Excavated for the first time in 1975-1976, the site was surveyed in detail by an archaeological mission more recently. This impressive ensemble of standing stone elements probably dates from the end of the 5th millennium BCE. It includes 54 groups of rudely trimmed stone pillars; six groups, displaying the best-preserved specimens, have been fenced by the authorities. Each group contains multiple pillars ranging from 2 to 4 meters high. The pillar stones were brought to the site from some yet unknown distant location, cut and shaped into the shapes seen today. The technique mobilized to perform this handiwork is still unknown.

The North-South axis alignment followed by most of the stone rows has been invoked to suggest an astronomical observatory function. As the erection of these massive megaliths, weighing around 5 tons each, required an evident effort from its builders, it has been argued that it occurred at a time when at least partial sedentary lifestyle — justifying such a heavy territorial investment — had developed. An astronomical observatory function would then make sense, as the understanding of seasonal cycle is of major importance for agricultural societies. The representation of celestial symbols in graffiti on other megaliths, like in Kurbat Tamathil, Tabuk, could support this theory. A funerary and ritual function is also possible: megalithic collective burial structures have been identified within the fenced area, and approximately 70 burial sites, dating from the 5th or 6th millennium BCE (mostly trench tombs, but also more elaborate multi-chambered cairn graves), are found outside the fence. Many stone tools such as scrapers, broths, blades, arrowheads, and fragments of other lithic tools and pottery have been excavated in the Rajajil archaeological site.

Harrat Khaybar

Harrat Khaybar is a lava plateau in the North-West of Saudi Arabia spanning across approximately 12,000 km2. Visited by human communities since prehistoric times, it displays an impressively rich corpus of stone structures including kites of various shapes, wheels, cairns, pendants and mustatil (notably near Samhah). It presents a uniquely high density of ancient stone structures mostly concentrated in the vicinity of the oases of Khaybar and Al-Ha’it and in a few outliers around the south-eastern and south-western fringes of the lava plateau (no stone structures are found in between). The archaeological vestiges of the Harrat are currently being explored and surveyed, while the ensemble of the plateau with its ancient volcanoes and lava caves, is being proposed as a UNESCO Global Geopark.

Harrat Rahat

The volcanic fields of the Harrat Rahat lie south of the Harrat Khaybar. With a 20,000 km2 surface, it is the largest lava field of Saudi Arabia extending for 300 km south of Madinah. This large lava filed probably counts many thousands of extremely various elements: including wheels, pendants, elongated triangular structures but also what is interpreted as primitive kites — less sophisticated and aesthetically harmonious than the ones in Khaybar. The size of several elements in Harrat Rahat is particularly remarkable, with an almost 4 km-long early form of kite endowed with a disproportionally elongated southern enclosure delimited by a triangular structure.

Harrat Kishb

Southeast of Madinah lies the volcanic fields of Harrat Kishb were various stones structures and more than 20 kites were identified by recent archaeological surveys. These kites partially differ from the ones of Khaybar: they are characterized by a shallow angle to the guiding walls and make use of the natural landscape to amplify their effectiveness as animal traps. Their builders took advantage of the natural landscape to carefully position the traps to achieve the maximum effect. Most of the kites found in Madinah/Kishb area show multiple phases of construction, attesting to long use and gradual improvement. While their chronology is still imprecisely known, it appears that these kites were in use over an extended period, which implies a long-lived hunting tradition and process of landscape modification. ‘Meandering walls’, interpreted as the earliest kinds of kite-like structure, have also been also identified in the area.

Harrat Lunayyir

The lava field of Harrat Lunayyir, located some 20 km northeast of the Red Sea port of Umluj, includes stone structures of various kinds — particularly rich in pendants and wheels — distributed in different zones of the lava field and usually clustered in little groups of a few elements.

Tabuk region

The Tabuk province is located in the northwest of Saudi Arabia. The footprint of prehistoric humans attests a human presence in this region possibly dating as far as 85,000 years ago. Numerous prehistoric remains ranging from rock and animal drawing in Kilwa, northeast of Tabuk, to artifacts from the Stone Age, bears witness of the relevance of Tabuk region in the prehistorical human occupation patterns. Stone structures are found in the region and complete Tabuk’s testimony. An important cluster of aggregated stone circles — imbricated over one another and interpreted as potential remains of human temporary or semi-permanent settlements — is included in the series.

Ha’it oasis

The province of Hail, in the North of Saudi Arabia, was a crossroads of ancient commercial roads leading to Mesopotamia and to the Levant. For centuries, the oasis of Al-Ha’it played a key role as a regional port of call. However, the province of Hail made a much earlier entrance into human history. The profusion of pendants and keyholes of various size, usually lying parallel to each other within extraordinary, concentrated areas, bears witness to the early presence of prehistoric communities, long before the development of the ancient Bronze Age northern Arabian civilizations.

Harrat Nawasif

Harrat Nawasif, some 250 km east of Makkah, is the southernmost among the major harrat-s (lava fields) of Saudi Arabia. It sits in a geographically significant area on the edge of the highland spine of western Arabia, a region characterised by relatively high rainfall, and known as the origin of ancient West-to-East flowing fluvial systems. This harrat hosts a very rich corpus of stone structures including kites, cairns, pendants, and wheels. Several hundred of kites are concentrated on its edges and along small wadis extending into the harrat. In its northern part, kites occur in considerable numbers in proximity of ancient shores of paleolakes. The kites of Harrat Nawasif generally present a simple shape, with two gently converging walls and cells only on the far distal end of the structure. They typically lack elaborate enclosures or features such as “barbs” (ancillary walls that jut away from the main convergent walls of a kite toward the open end like the barbs of an arrowhead). They considerably vary in size: many are very small, but one kite has a length of around 1,400 m. With its 3,000 linear metres of walls, and enclosing an area of over 500,000 m2, this kite is among the largest ever identified.


The Hisma mountains, west of Tabuk, were crossed by one of the oldest and most frequented ancient commercial routes. An important quantity of stone structures, notably circular stone structures and cairns, are found in this area alongside other prehistoric, antiquity, and early Islamic vestiges (including Thamudic inscriptions and graffiti). Circular stone structures have various dimensions and designs ranging from nearly 140 m diameter to just a few meters. They can be isolated mono-structure or clustered to form several imbricated circles. The long-standing utilization of the Hisma mountain corridor across time, led to the formation of a unique landscape where successive generations have extended the work of prehistoric communities and let their own footprint into the landscape. In this deserted passageway, ancestral circular burials coexist next to graves of merchants and Muslim pilgrims who took the same path several millennia later. This extraordinary continuity and historic layering constitute the most outstanding dimension of the Hisma heritage.

Al Faw, piedmont of Jabal Tuwaiq

Al-Faw, situated at the north-western fringe of the Empty Quarter, stands at the intersection of Wadi Ad-Dawasir and the Tuwaiq escarpment. An outstanding collection of prehistoric stone structures of different shape and size is found at the foot of the cliffs and on the plateau. More than 1,500 circular stone structures (notably cruciform tombs / “wheels” of 25 m diameter) are found in the wadi, concentrated in a 4 km2 sector.

Justification de la Valeur Universelle Exceptionnelle

The Prehistoric Stone Structures in Saudi Arabia serial property presents the multifaceted contribution of Arabian prehistoric human societies to the development of early civilizations through an increased sense of territoriality and emotional attachment to ancestral pastures, the development of hunting techniques and possibly the first seeds of farming, the elaboration and transmission of skills and knowledge, ranging from geometrical and architectural skills to astronomical observation, and community-building around symbolic and ritual practices.

The elements of the series share an extraordinary monumental scale and a similar geometric layout and aesthetics, notwithstanding their different shapes (that played different functions in ancient human societies) and their belonging to different construction periods typifying successive cultural traditions. They reveal a much deeper level of complexity than was previously acknowledged. This architectural sophistication mirrors a rich prehistoric culture where religious and collective rituals seem to have played a major role.

Mustatil-s illustrate this aspect as they most probably played a strong ritual role as open-air structures where the community would enter in procession through the narrow entranceway and access the platform topping the two long parallel wall sides, where niches were endowed with offerings.

The dimension and concentration of stone structures constitute an essential clue of the gradual sense of territoriality developed by the Prehistoric communities that finally resulted in a sedentary or semi-sedentary way of life. The immense kites included in the series, interpreted as animal traps, probably required several months to be built by early human communities. It is therefore likely that their builders would seasonally come back to benefit from this huge investment: participating in a sedentarisation process as well as in the beginning of breeding practices through systematic large captures of wild animals. The ingenious design and location of the kites, allowing an optimization of hunting, represents therefore a major innovation and an outstanding example of prehistoric hunting practices deployed by ancient communities to meet their food needs.

While the level of community engagement and efforts required for their construction is evident, much work is still needed to understand the full complexity and purpose of Arabian monumental prehistoric stone structures. Their potential Outstanding Universal Value is indissociable from their impressive number and spectacular scale which made them fully appreciated only when aerial images began to capture their shapes from the sky.

Arabia hosts one of the earliest large-scale forms of monumental stone structure construction anywhere in the world, still largely unresearched. The elements of the Prehistoric Stone Structures in Saudi Arabia constitute an inestimably precious bridge to connect to still unknown prehistoric cultures.

Criterion (i): The sheer monumental size and outstanding number — roughly estimated to 1 million in Saudi Arabia — of the prehistoric stone structures included in the serial property, and the creativity of their builders who constructed an astonishing variety of geometrical shapes of cairns, pendants, mustatil, circular structures, and kites bear witness to the extraordinary level of sophistication of these ancient architectural structures that represent early masterpieces of human creative genius. While from the field it is not always easy to fully appreciate their careful and precise geometrical aesthetics — as their construction walls are usually less than 1 m high, and they are mostly located within rocky plateaus — aerial views fully reveal the fascinating technological ingenuity and the quality of these monumental structures created by ancient human communities in Arabia.

Criterion (ii): Since the first discovery of stone structures in the territories of modern Jordan and Syria, the large geographical scope of the stone structures has stood as one of their most remarkable features. The elements of the Prehistoric Stone Structures in Saudi Arabia serial property are clearly rooted in a broader regional tradition while demonstrating the continuous evolution of practices through regional interchanges amongst different human groups. The diversity of design of the mustatil-s, kites, circular stone structures and the various types of pendants, illustrate the creativity and continuous improvement of a long-established constructive tradition. The multiple forms of the kites included in the serial property likely result from continuous innovation efforts aiming to increase the efficacy of animal traps. The diverse geometrical forms of the cairns and pendants, and the presence of a varying addition of paralleled walls observed among the “gates”, illustrate a rich mosaic of aesthetic and ritual practices. This extraordinary diversity of forms does not veil the striking cultural and constructive homogeneity of the prehistoric stone structures over a large territory. No less than 700 km separate the Azraq oasis of Jordan, where numerous wheel stone structures and kites were discovered, from Harrat Khaybar, while similar stone structures are found also in the South of Saudi Arabia in Al-Faw, almost 900 km from Harrat Khaybar. The stone structures edification was doubtlessly a long process that probably took hundreds of years. The transmission of the constructive techniques, and their gradual improvements over time, constitute a unique example of long-term human interchanges across space and time.

Criterion (iii): The Prehistoric Stone Structures in Saudi Arabia serial property demonstrates — contrary to a common assumption considering that Arabia’s harsh climate made this territory unsuitable for human presence and development — that the Peninsula was largely inhabited throughout millennia. The variety and complexity of the stone structures greatly increase the understanding of the prehistoric civilizations in the Peninsula and shed light on a largely unknown Arabian prehistoric past. While the local Bedouin communities are familiar with the existence of these stone structures, known as the “Work of the Old Men”, scientific research is still largely in its infancy. Their inclusion in the Saudi Tentative List for UNESCO acts as a catalyser to develop research and renew efforts and studies on these structures.

Criterion (iv): The Prehistoric Stone Structures in Saudi Arabia are the oldest monumental remains left by prehistoric human communities in Arabia. They mark an important step in the development of architectural competences, but also of astronomical knowledge, necessary to any society in the process of an agricultural transition. The construction of these structures also demanded a strong community sense, to deploy the collective efforts necessary to build non-movable structures in specific places, and therefore proves the early existence of social organization forms and the collective adherence to an authority surpassing the individuals. The creation of a community identity is materialized by the construction process itself as well as by the ritualistic nature of several of these structures that possibly introduced a new sense of territoriality paving the way for sedentary, or semi-sedentary, ways of life.

Déclarations d’authenticité et/ou d’intégrité


There are hundreds of thousands of prehistoric stone structures built at different periods of time in Saudi Arabia. The proposed serial property focuses on a selected corpus of monumental elements which appear as the best-preserved and most significant testimonies of the evolutive practice locally known as the “Work of the Old Men”. This corpus bears the potential to include the ensemble of attributes that will “truthfully and credibly express the cultural values of the serial property”.

The stone structures of the series have been let untouched since their abandonment. They have all retained their original location, setting, materials form, and design. Their extraordinarily preserved form and design, and their original materiality, are the main attributes expressing their potential Outstanding Universal Value. It has been suggested that some specimens went through partial reconstruction or stone reuse at a time when prehistoric stone structures were still in use. This seems the case for the kites found in Harrat Kishb, that are sometimes intertwined with later structures and that were apparently built over several construction phases. Future studies will aim to ensure that all the elements of the series, their relations to each other, their dating, and their function and signification are better understood within an integrated approach.

Ongoing and future research will permit to finetune the selection of the elements to guarantee that the selected stone structures fully represent their architectural quality, and their social relevance in human history as possible catalysers for the development of agriculture through astronomical knowledge, herding, and attachment to ancestral pasture.


The geographic distribution of the 10 selected elements of the series mirrors the impressive geographical scope of the monumental stone structures, which contributes to their potential Outstanding Universal Value. The proposed clusters included in the series are of adequate size to ensure the complete representation of the features and processes which convey the property’s significance, and the elements of the series are not affected by modern development nor by vandalism.

The relative remote location of the corpus of large stone structure, found abundantly in uninhabited volcanic fields and desert areas across the Arabian Peninsula, enabled an exceptional degree of preservation of hundreds of thousands of stone structures of different size and shape. The stone structures specimens are therefore very well preserved. Most of them seem untouched and display a complete and unbroken circular, kite, and rectangular (mustatil) design, with all their features intact.

The integrity of the elements in the landscape, that is essential to understand their function, relevance, and distinctive character, is also exceptionally preserved. The elements of the series constitute clusters of highly concentrated specimens which have preserved their relationship with their surroundings. Only the site of Rajajil is close to contemporary agricultural development. While some of its prehistoric remains have been affected by the agricultural expansion, the most relevant megaliths, protected by a fence, and the funerary landscape of the immediate site area are intact.

All the elements of the Prehistoric Stone Structures in Saudi Arabia series show an extraordinary level of preservation, integrity, and authenticity and none of them has undergone modern modifications and/or partial reconstructions.

Comparaison avec d’autres biens similaires

The Outstanding Universal Value of the Prehistoric Stone Structures in Saudi Arabia serial property lies in the scale, geographical scope, design, evolution through time and space, and exceptional connection with still unknown prehistoric cultures, that characterize the series as an ensemble. Each component of the series brings to light specific clues about the peoples who created these structures and constitutes a testimony of a complex and sophisticated aesthetics, possibly deployed to comply with ritual and pragmatic functions.

The comparative analysis is developed along three axes, addressing different aspects of this serial property. A first set of comparison relates to other Megalithic structures in the World Heritage List or in national Tentative Lists, mostly located in Europe.

Stonehenge, Avebury, and Associated Sites (United Kingdom, 1986, criteria i, ii, iii): Stonehenge and Avebury, in Wiltshire, are among the most famous groups of megaliths in the world. The two sanctuaries consist of circles of menhirs arranged in a pattern whose astronomical significance is still being explored. These holy places and the nearby Neolithic sites are an incomparable testimony to prehistoric times.

Megalithic Temples of Malta (Malta, 1980, criterion iv): Seven megalithic temples are found on the islands of Malta and Gozo, each the result of an individual development. The two temples of Ggantija on the island of Gozo are notable for their gigantic Bronze Age structures. On the island of Malta, the temples of Hagar Qim, Mnajdra and Tarxien are unique architectural masterpieces, given the limited resources available to their builders. The Ta'Hagrat and Skorba complexes show how the tradition of temple-building was handed down in Malta.

Brú na Bóinne - Archaeological Ensemble of the Bend of the Boyne (Ireland, 1993, criteria i, iii, iv): The three main prehistoric sites of the Brú na Bóinne Complex, Newgrange, Knowth and Dowth, are situated on the north bank of the River Boyne 50 km north of Dublin. This is Europe’s largest and most important concentration of prehistoric megalithic art. The monuments there had social, economic, religious, and funerary functions.

Carnac Megalithic Sites (France, Tentative List 1996, criteria not specified): The remains of megalithic civilizations (dating from 5,000 to 2,000 BCE) are scattered in the county of Morbihan and in the town of Carnac. Carnac hosts a unique set composed of three alignments of megaliths, one of which (called Le Ménec) displays an original composition made up of two enclosures and rows of aligned menhirs or standing stones. The ensemble, made up of 4,000 menhirs stretching over nearly 4 kilometres and 40 hectares, is completed by a covered alley, a cromlech of isolated menhirs in the North and a very large tumulus in the South, representative of the Carnacean-typed tumulus (125m x 60m x 12m high) and a passage dolmen.

Megalithic sites are found in Asia, Africa, Europe, America, and Australia. They reveal many cultural aspects of the life of our ancestors. They reflect the development of ancient human communities and their very sophisticated ability to plan and implement large-scale projects. Megalithic structures are often associated with the Neolithic revolution.

The megalithic Rajajil standing stones are an important addition to a global prehistoric world-tradition that connects the Prehistoric Stone Structures in Saudi Arabia to other prehistoric sites worldwide. While European sites have attracted the attention of historians since more than a century, the scientific attention paid to the Saudi sites is very recent and opens promising opportunities for further research to better understand the still unclear function of the megaliths (funerary, astronomical…), as well as their construction process.

The inclusion of the megaliths of Arabia within a broader serial property, on the other hand, underlines the cultural synergies of the different prehistoric stone constructions found in Arabia, connecting them to the developing sense of territoriality, community building and architectural ambition characterizing the end of the Neolithization process.

A second set of comparisons can be drawn with large-scale surface drawing sites.

Lines and Geoglyphs of Nasca and Palpa (Peru, 1994, criteria i, iii, iv): Located in the arid Peruvian coastal plain, some 400 km south of Lima, the geoglyphs of Nasca and the pampas of Jumana cover about 450 km2. These lines, which were scratched on the surface of the ground between 500 BCE and 500 CE, are among archaeology's greatest enigmas because of their quantity, nature, size, and continuity. The geoglyphs depict living creatures, stylized plants, and imaginary beings, as well as geometric figures several kilometres long. They are believed to have had ritual astronomical functions.

Despite very different contexts, the Lines and Geoglyphs of Nasca and Palpa property shares similar attributes with the proposed nomination. In both cases, the monumental feature of those properties, their geographical scope and large distribution over the territory, and their amazing artistic sense can be better appreciated remotely from above. Additionally, both sites were developed by long-since disappeared cultures and are still only partially understood by the international scientific community. Notably, it is still unclear which cultures built them, what they meant to the communities who elaborated them, and what was their functional use. Those similarities should nonetheless not veil the differences that constitute both sites’ uniqueness. The Prehistoric Stone Structures in Saudi Arabia are a much older monumental ensemble and their meaning in the larger context of human evolution is therefore different. As very ancient traces of monumental territorial investment, they show an increased sense of territoriality, precursor to sedentarism, and they evidence the early ability of humankind to shape and modify its environment so heavily that its intervention remains visible millennia later. The ambition of the Prehistoric Stone Structures in Saudi Arabia is unprecedented. While the Lines and Geoglyphs of Nasca and Palpa were drawn by scratching the soil and could be transmitted to present generations thanks to the desert climatic conditions, the Saudi structures were built of stones, collectively gathered or shaped, and transported and disposed by their builders, over hundreds of meters. The Prehistoric Stone Structures in Saudi Arabia illustrate a unique cultural tradition.

A last set of comparison refers to prehistoric burial landscapes in the World Heritage List:

Heart of Neolithic Orkney (United Kingdom, 1999, criteria i, ii, iii, iv): The group of Neolithic monuments on Orkney Islands consists of a large chamber tomb (Maes Howe), two ceremonial stone circles (the Stones of Stenness and the Ring of Brodgar) and a settlement (Skara Brae), together with many unexcavated funerary ceremonials, and settlement sites. This group constitutes a major prehistoric cultural landscape which gives a graphic depiction of life in this remote archipelago in the far north of Scotland some 5,000 years ago.

Archaeological Sites of Bat, Al-Khutm and Al-Ayn (Oman, 1988, criteria iii, iv): The protohistoric site of Bat lies near a palm grove in the interior of the Sultanate of Oman. Together with the neighbouring sites, it forms the most complete collection of settlements and necropolises from the 3rd millennium BCE in the world.

The Heart of Neolithic Orkney and the Archaeological Sites of Bat, Al-Khutm, and Al-Ayn properties offer fascinating clues about pre-historic burial traditions, which find an echo in the cairns and funerary pendants included in the Prehistoric Stone Structures in Saudi Arabia serial site. The Omani tower tombs, notably, closely resemble to some elements included in the serial Saudi property. Their inclusion in a larger and more complex uninterrupted historic sequence, however, connects them with both earlier and successive traditions, providing new insights on the 3rd millennium human communities in the Arabian Peninsula.

The Saudi Arabian serial property adds a new, impressive funerary corpus, characterized by a very rich and distinct aesthetics and impressive dimensions, and offers new important elements illustrating the diversity of ancient human funerary practices at the global level.