Bara Gumbad 15th century Islamic structure, Lodi Gardens, Delhi

Bara Gumbad & mosque, Delhi Lodi gardens. Flickr

Bara Gumbad (meaning "big dome"), built  in 1490 CE, during the reign of the Lodhi dynasty is  in Lodhi Gardens, Delhi, India. Being part of a group of monuments that include a Friday mosque (Jama Masjid) and the "mehman khana" (guest house) of Sikandar Lodhi, it is believed to have the earliest well-built full dome of any building in Delhi.

The monument is  close to the Tomb of Sikandar Lodhi and Shisha Gumbad and they share a common raised platform, built at different time during the Lodhi reign; they were not constructed at the same time. The absence of a tombstone questions the intended purpose of this structure. The raised platform suggests that it was to be a burial place.
The place where the Bara Gumbad is located was earlier called Khairpur.

Bara Gumbad mosque, Delhi. Wikimedia Commons

According to  the inscription in a  mihrab (prayer niche) in the Friday mosque (Jama Masjid) of the Bara Gumbad,  the date of construction is given as  900 AH (Anno Hegirae) of the Islamic lunar calendar. There are four monuments in the Lodhi Gardens, including Bada Gumbad;  the other three being Tomb of Sikandar Lodhi, Shisha Gumbad and the tomb of Muhammad Shah ( of the Sayyid dynasty). The purpose of the Bara Gumbad  remains a  riddle. Might have been a gateway to the Friday mosque!!  The Friday mosque that came up in 1494 CE was the first mosque  built in a style relevant  during the Lodhi Dynasty. It is believed Bada Gumbad was initially built by a noble man in 1490 CE, later it was taken over by Lodi  in 1494 CE, to provide an entryway to his mosque. As one may see, these monuments were built  independently, and it was in early 20th century a park was laid out, bringing all the monuments within one confine. On 9 April 1936, Lady Willingdon, the wife of Viceroy Lord Willingdon inaugurated the park and was originally called the Lady Willingdon Park after her. After India's freedom from the British in 1947,  it was renamed Lodhi Gardens after the early rulers.

Carvings on the exterior, Bada Gumbad Mosque

All the structures are constructed on a 4 metres (13 ft) high platform, with a total area of 1,050 square metres (11,302 sq ft). The platform measures 30 metres (98 ft) (east-west) and 25 metres (82 ft) (north-south).   It is a semi-circular turreted Mosque with three  out of five bays in the mosque have domes whereas the remaining two have vaulted roofs (on mosque and "mehman khana").

The Bara Gumbad is a square type Hindu-Islamic structure which rests on a plinth. It is  29 metres (95 ft) high, 20 metres (66 ft) long and 20 metres (66 ft) wide. The walls are 12 metres (39 ft) tall. The mosque measures 20 meters (66 feet) on all sides. Like the 
Shisha Gumbad   the Bara Gumbad is also a single story structure but, it looks like spanning in two floors when viewed from outside. Total floor area of Bara Gumbad (excluding the mosque and the guest house) is 361 square metres (3,886 sq ft).

The dome, the mosque and the " mehman khana" are made of red, grey and black stone, including grey quartzite and red sandstone. The interior  well-ornamented with painted stucco, has colored tiles, incised carvings, and painted plaster on the mosque, decorated with foliage, flowers, geometric patterns, and Quranic inscriptions.