It is said that when Iltumish inspected the site the day after his dream, he reported to have found a hoof print of Prophet Muhammad's horse. He then erected a pavilion to mark the sacred location and excavated a large tank around the pavilion to harvest rain water.
Another version of the legend says that the Holy Prophet appeared in a dream not only to Iltumish but also to the sufi saint Khawaja indicating the same location where the hoof print of Prophet's horse was imprinted. 
Since drinking water supply was acute in the newly founded capital of Iltumish (the first medieval city of Qila Rai Pithora ) a tank was dug at the location indicated in the dream, which resulted in water jetting out from a spring source.
It was, thereafter, named as Hauz-i-Shamsi, and Khawaja, the saint who divined it, came to be known as Hazrat Qutbuddin Bakhtiar Kaki or simply 'Kaki'. The name Kaki was attributed to him by virtue of this keramat (miracle).
Jahaz Mahal was built on the eastern edge of the same reservoir during the Lodi dynasty period in the 16th century as a retreat or Inn for use by the pilgrims. 
Also at the edge of Hauz is the tomb of 17th century Persian writer in the Mughal court,Abdul-Haqq Dehlavi.
