The first tomb of Delhi or the first surviving tomb of an Islamic ruler is situated in the Qutb Complex. It is the tomb of the successor and son-in-law of Qutbuddin Aibak as well as the second sultan of the slave dynasty, Iltutmish. This mausoleum was built by him in 1235, lying in the north-western corner of the complex. He made his tomb near the extended Quwwat-ul-Islam mosque. The credit of the extension of the mosque was also done by him. In the centre of the structure, his tomb exists on a raised platform. The cenotaph is in white marble. The tomb also used to have a dome but it has now disappeared.
It is a square structure, measured 9 meters from all sides. For the outside it is very simple, no design, decoration, etc. have been done on the outer wall of this monument. While the interior was totally opposite to the exterior. The inner portion is highly decorated. Quartzite was used in its construction which was faced with red sandstone. The structure can be entered from three sides and the western side, which faces Mecca, has a mihrab. In the decoration Islamic as well as Hindu decorations were used. Its interior is carved with geometric and floral patterns, Arabic inscriptions and the designs of lotus, kalash, etc. can also be seen.
