Udon Thani (Thai: อุดรธานี, pronounced [ʔù.dɔ̄ːn tʰāː.nīː]) is one of the four major cities (Khorat, Ubon Ratchathani, Udon Thani, and Khon Kaen) of the Isan region, Thailand, (known as the "big four of Isan"). It is the capital of Udon Thani Province.