At the far east of the Humayun's Tomb complex stands a much smaller structure. This is, nevertheless striking by the virtue of its shiny turquoise blue dome. Passing by the Nizamuddin East road, no one knows who was buried in it, when exactly was built or by whom, as it remains to be a historical mystery. Yet, the tomb is believed to be the oldest ruin and tomb in Delhi. It is believed to be there some 500 years before Humayun's Tomb.
At the time of construction, it was covered with blue, green and white tiles. The blue, gleaming as most dominantly. The dome is made of turquoise blue tiles thus giving it the name 'Neela Gumbad' or the blue dome.
In the 19th century, as the Nizamuddin station came up, the northern part of the monument was taken over. Further, in the 1980s, a road was built bifurcating the Nila Gumbad from the Humayun's tomb complex.
Thereafter, the monument came to be occupied by a squatter settlement with over 200 jhuggis. The inhabitants of the settlement were relocated in 2005-06.
Finally, an agreement was made in 2014 with the railways to shift the wall bifurcating the tomb from the Humayun complex, so that the visitors could appreciate the Nila Gumbad as part of the Humayun's complex. After
this the Aga Khan Trust for Culture (AKTC) took up restoration work bringing back some of its lost glory.
According to AKTC, restoring the blue tiles was a major challenge. Nearly 15,000 of them were missing. For this, the team had gone to Iraq but still could not find the original ones. Later, they were recreated in kilns constructed in the complex and employing youth from Hazrat Nizamuddin Basti. In the process, reviving a lost art tradition.
During restoration, The ceiling of the mausoleum was restored to reveal stunning artistic creations, the missing sandstone lattice screens were restored, and the land recovered from the railways was redeveloped in a
way to recreate (at least a part of) the original garden surrounding the mausoleum.
The monument was declared a UNESCO world heritage site as part of the Humayun's tomb complex in 2017. Now, it makes for an additional attraction for visitors of the Humayun complex.