Purana Qila (Old Fort)

Believed to be the site of Indraprastha, the original city of Delhi, the fort was built by Sher Shah Suri and completed in 1545 AD. Shortly thereafter, the fort was taken over by Humayun, who used the octagonal red sandstone tower Sher Mandal as a library and observatory. It was from the second storey steps that Humayun was supposed to have slipped to his death.
The small lake on the premises offers boat rides during summer.