The tomb of Shah Rukn-i-Alam was built by the Tughluq ruler of Delhi, Ghiyas-ud-din (r. 1320-1325), between 1320 and 1324 AD. Although probably intended as a mausoleum for is own dynasty, it was presented to the family of the renowned Sufi saint following the latter’s death. The three-tier structure stands within its own compound at the north-western edge of the Fort. It is octagonal in shape with an interior diameter of 15 metres and the first tier’s 4 metre thick walls assisted by 8 engaged corner towers or buttresses with a clear slope, support an 8 metre octagon surmounted by a dome with a diameter of 15 metres. The 35 metre high structure is constructed in red brick with a visible framework of beams of shisam wood. The exterior is further ornamented with the use of carved brick and wood as well as blue and white faience mosaic tiles with raised relief patterns. The octagon is decorated with geometric, floral and arabesque designs and calligraphic motifs. The interior, although originally plastered, is bare and the sarcophagus of the saint is surrounded by those of 72 of his descendants. The saint is still revered today and his tomb is the focus of the pilgrimage of over 100,000 pilgrims from all over South Asia who visit and commemorate his memory. The carved wooden mehrab is though to represent the earliest example of its category.