Cluj-Napoca, or simply Cluj, is the second-most populous city in Romania and the seat of Cluj County in the northwestern part of the country. Geographically, it is roughly equidistant from Bucharest (445 km), Budapest (461 km) and Belgrade (483 km). Located in the Someșul Mic river valley, the city is considered the unofficial capital of the historical province of Transylvania. For some decades prior to the Austro-Hungarian Compromise of 1867, it was the official capital of the Grand Principality of Transylvania.