This is the cenotaph of the foundress and two of her daughters of the Hunat Hatun Külliyesi: the usual complex of mosque, medrese and mausoleum. It was founded in 1235-38 by the Seljuk sultan Alaeddin Kaykobad's favorite Mahperi.
Sony Cybershot 1/320s f/4.0 at 9.7mm iso100
full exif