It was built in 1417-1418 by Çelebi Sultan Mehmet as a foundation for the Old Mosque. It is a 14-domed building with ornamented walls covered with two-coloured, cut stones. The domes are covered with lead. Measuring 40.54-74.94 metres, the building has doors on four sides. There is a pointed arched window under each dome. Inside, there are 14 vaulted cells on the long sides and 4 cells on the short sides. Evliya Çelebi writes that the diamonds and jewellery in the bedesten are worth several Egyptian treasures and that sixty night guards protect them. The bedesten, which has been repaired in recent years, is now used as a bazaar.