The complex of Yildirim was composed of an iwan type of masque-convent, a madrasa, the turbeh of Bayazid I, a hamam, an imaret, a darussifa, and a palace. The mosque was begun in 1390 and completed in 1395. All three iwans of the Mosque are domed. There are four convent rooms placed on either side of the auxiliaxy iwans. All four of the rooms are covered by flat-topped cross vaults and are furnished with fireplaces and storage niches. The dome of the main iwan is placed on a belt of Turkish triangles. Others rest on triangular comer panels and the transition to the main dome is effected through squinches. The iwans are raised three steps from the central hall. This mosque is constructed entirely of cut stone. Except for the frames of the two rear windows, which come from a Byzantine building, this mosque contains nothing-derived form a foreign source.