The Hiran Minar ("antelope tower") is located north and west of the Hathi Pol, outside of the palace complex, just north of the imperial caravanserai. Measuring twenty-one meters in height, the tower's plan is octagonal at its base, circular after the height of 3.91 meters, and topped with a chhatri. The circular part of the tower is decorated with stone spikes, and a circular balcony projects on stone corbels from the upper part of the tower.
Its exact function is unknown, but it may have been a lookout tower or a distance marker for travelers.
Sources:
Nath, R. "Fatehpur Sikri." In Grove Art Online. Oxford Art Online,
http://www.oxfordartonline.com/subscriber/article/grove/art/T027637 [Accessed October 8, 2010].
"Fatehpur Sikri Hiran Minar." Agra India website.
http://www.agraindia.org.uk/fatehpur-sikri/hiran-minar.html [Accessed October 8, 2010].