Ubon Ratchathani, commonly referred to as Ubon, is a city located in northeastern Thailand. It serves as the administrative center of Ubon Ratchathani Province and is situated on the north bank of the Mun River.
The city is recognized as one of the four largest cities in the Isan region, alongside Nakhon Ratchasima, Udon Thani, and Khon Kaen. These four urban centers are collectively known as the "big four of Isan."
Geographically, Ubon Ratchathani is located approximately 497 km (309 mi) from Bangkok in a straight line, or roughly 629 km (391 mi) when traveling by road.