Partially an annex of Hagia Sofia's baptistery, there are 5 tombs of sultans and princes. Each architecture has different decorations, including works by Mimar Sinan. The entry is difficult to see, but look to the water side of Hagia Sofia, just before the vendor stalls begin. Although it is next to Hagia Sofia, the site is not crowded and tranquil. Eachy of the five tombs actually houses the sultan as well as his family. The tile work alone is worth the detour. Remove your shoes before admission.  Admission free.