Firuz Shah (r. 1351-88) of the Delhi-based Tughlaq dynasty was a sultan interested in architecture. He is known for having built various schools, religious establishments, and earthworks.
His tomb is in the middle of a madrasa he commissioned, overlooking a tank of water known as Hauz Khas. The tomb's plain style is faithful to the austerity of much of Tughlaq building. The simple 15 foot square structure is built of ashlar walls finished with lime plaster with arched entrances and merlons along the parapet. Above the parapet rises an octagonal drum, which supports a shallow and slightly pointed dome. The north and west of the tomb are contiguous with one of the wings of the madrasa. To the east are several chattris, small domed structures supported by pillars, which house tombs of saints and religious teachers. The tomb has a low platform to the south that is enclosed by a graceful stone railing.
Internally the tomb measures 29 feet (8.74 meters) and is paved with gray stone slabs. The intrados and ceiling of the dome are embellished with colored bands that intersect each other. The squinches are decorated with plasterwork including incised calligraphy. The designs have been incised and gorgeously painted in dark red, green and turquoise. The medallions, Quranic verses, and floral designs combine to describe paradise.
The tomb contains four unmarked graves; three are made of marble and the fourth, near the east door, is of rubble and plaster. The central grave is that of Firuz Khan. It measures nine by six feet and over two feet in height (three by one and a half meters and over half a meter in height). The other two marble graves, which are similar to the central one, are ascribed to the son and grandson of Firuz Shah, Nasiru'd-Din Muhammad Shah and Alau'd-Din Sikandar Shah.
Sources:
Alfieri, Bianca Maria. 2000. Islamic Architecture of the Indian Subcontinent. London: Laurence King Publishing, 43.
Rani, Abha. 1991. Tughluq Architecture of Delhi. Delhi: Bharati Prakashan, 49,50.
Asher, Catherine. 1992. The New Cambridge History of India: Architecture of Mughal India. Cambridge University Press, 8-9.
Nath, R. 1979. Monuments of Delhi. New Delhi: Ambika Publications, 41.