The Türbe (mausoleum) of Devlet Hatun, the 12th wife of Bayezıd I and the mother of Mehmed I.
She was born in 1365 to an Anatolian prince, II. Yakup Bey, a ruler of the Anatolian Germiyan dynasty ( Kütahya). She was also a descendant of Celaleddin Rumi, founder of the Sufi order of Melevis, through his son Sultan Walad, whose daughter Mutahhare Abide Hatun was her mother. The impressive lineage of Devlet descended from the powerful princes and charismatic sheikhs.

The marble grave monument dates from 1414. It is square (5,75 x 5,75 m), open on all four sides and covered by a dome placed on a high cylindric drum.

Correspondent: J.M.Criel, Antwerpen.
Sources: ‘Vakıf Abideler ve eski Eserler (volume III)’ - Vakıflar Genel Müdürlüğü, Ankara 1983 ; Wikipedia
& Website of ‘banagelenmail.com’ .

Please note: I took this picture on a walk I made from the Blue Mosque to the Yıldırım Mosque. However, it lies closer to the former, and does not belong to the Yıldırım complex.