Syed Altamash Ahmad

  Qila-i-Kuhna Mosque meaning Mosque of the Old Fort is a single-domed mosque located inside the Purana Qila in Delhi. The Tarikh-i-Sher Shahi by Abbas Sarwani, says that the mosque was built by Sher Shah Suri built in 1540. Some historians believe that the mosque was originally built by Humayun and its upper part which includes its dome, was built by Sher Shah Suri. However, The architectural work inside the mosque neither matches Sur nor Humayun's work.  Some of the similar work can be found in the tomb of Ibrahim Khan Sur built by Sher Shah Suri but the use of geometric works on its marble wasn't famous at that time and was probably added later by Akbar. 

  Humayun Darwaza is one of the 3 existing gates in Purana Qila, Delhi. The huge gate is situated in a dilapidated condition at the southern part of the fort.  There are two schools of thought regarding who built this gate. Some historians believe the gate was a part of Dinpanah built by Humayun. Others believe after defeating Humayun, Sher Shah Suri demolished every part of the fort and established this gate as a part of his fort 'Shergarh', and Humayun just renowned it after he recaptured the fort.  However, the gate is now known as Humayuni Darwaza, probably because the tomb of Humayun is visible from the top of the gate.