Ulu Cami is the largest mosque in Bursa and a landmark of early Ottoman architecture, which incorporated many elements from Seljuk architecture. Ordered by Sultan Bayezid I, the mosque was designed and built by architect Ali Neccar in 1396–1400. It is a large and rectangular building, with a total of twenty domes that are arranged in four rows of five, and are supported by 12 columns. Supposedly the twenty domes were built instead of the twenty separate mosques which Sultan Bayezid I had promised for winning the Battle of Nicopolis in 1396. The mosque has two minarets.