The Brooklyn Bridge is a large-scale steel and stone cable-stayed suspension bridge with a central span of 1,595 feet (486m) and a toal length of 5,989 Feet (1,25m). Completed in 1883, it spans the East River to connect the New York City boroughs of Manhattan and Brooklyn. It is owned, operated, and maintained by the City of New York’s Department of Transportation, and has remained in active use since its completion, carrying cars, pedestrians and bicycles. Until the mid-20th century, it also carried elevated trains and streetcars. The property covers approximately 20 acres (8 ha).
The Brooklyn Bridge is an outstanding large-scale suspension bridge of the modern era, remarkable both technologically and in its aesthetic expression. At the time it was built it was the longest suspension bridge in the world and its construction was significantly innovative as the first of its kind to use steel cables and the first large-scale use of the French pneumatic caisson method, as well as using an ingenious method for stiffening the deck. The bridge’s imposing stone towers complement the steel catenaries and cable stays to yield one of the most famous and globally known monuments of New York City, representing the city’s growth and development in the second half of the 19th century.
Criterion (ii): The late 19th century was a period of great activity, innovation and progress in the construction of large-scale bridges, particularly in Europe and North America. The innovations made by the Roebling family in solving technical issues posed by a suspension bridge of this size built on the active exchange of knowledge among engineers and designers of the time. The resulting innovations found in the Brooklyn Bridge in turn set new standards of practice in the field of bridge construction, particularly for suspension bridges.
Criterion (iv): The Brooklyn Bridge is an outstanding example of a type of technological ensemble, the large-scale suspension bridge, that was a milestone in their design and construction. Features such as the use of steel cables and the large-scale use of the French pneumatic caisson method were significant innovations for suspension bridges. It was a peak achievement in a period of rapid advancement in large-scale bridge engineering, responding to the needs of rapidly industrializing and urbanizing societies. The bridge’s highly visible location in the heart of New York City serves to emphasize this role.
The essential attributes and features of the bridge that relate to its Outstanding Universal Value have remained intact. These include in particular its central and approach spans, caissons, Gothic-arched stone towers, anchorages, steel cables, road deck and elevated walkway. As an active and important transportation feature in a major city, the bridge has experienced some changes over time, but these are relatively minor in nature. As a registered New York City Landmark since 1967, the bridge is subject to careful review of any planned work to ensure it is appropriate for the structure.
The attributes of the Brooklyn Bridge that help to convey its Outstanding Universal Value are its size, form and design; construction techniques; materials; functions; and location and setting. As the bridge has functioned continuously for its original purpose, these attributes are able to continue to convey the original values. Some physical changes, primarily on the deck of the bridge, have accommodated changing transportation needs over time, such as the removal of train and trolley tracks in the mid-20th century in favor of additional lanes for cars; similar adjustments would be expected to enable the bridge to continue to serve a vibrant city. Some elements in the setting have of course changed as well, as the scale of buildings has gradually increased, but the Brooklyn Bridge has maintained its power and presence.
The Brooklyn Bridge was included in the Context for World Heritage Bridges prepared by ICOMOS and the International Committee for the Conservation of Industrial Heritage (TICCIH) in 1996. This study, which is both thematic and comparative, assessed global bridges chronologically by material and by type, and identified bridges considered to have potential for World Heritage inscription. Among these are eleven suspension bridges, including the Brooklyn Bridge, and includes the statement that “[f]ew bridges in the world built since the Brooklyn Bridge in New York (USA) can stand entirely clear of its shadow.”
ICOMOS also noted in its upstream assessment of this property in 2016 that there are very few bridges from the modern era on the World Heritage List or even on Tentative Lists. The Forth Bridge in the United Kingdom was inscribed in 2015, though it is a cantilever truss rather than a suspension bridge. Although the Context for World Heritage Bridges appears to provide a strong comparative basis to support the Outstanding Universal Value of the Brooklyn Bridge, further work would be beneficial, both to update the Context with more recent scholarship and conservation information, and to compare the Brooklyn Bridge more systematically with other comparable bridges defined in various ways based on the proposed Outstanding Universal Value.