Pir Ghaib Hunting Lodge and Observatory is a medieval building in Delhi, India. It is believed to be built by Sultan Firuz Shah Tughlaq of the Delhi Sultanate in the 14th century. It is a double storied structure and, just like most other examples of Tughlaq era architecture, is made up of rubble. The building has a hollow masonry cylinder, which is believed to have been used for astronomical purposes. Apart from its theorized uses as a hunting lodge and observatory, it is also believed to have been used as a clock tower