Tromsø city is the ninth-largest urban area in Norway by population, and the seventh largest city in Norway by population. It is the largest city and the largest urban area in Northern Norway, and the second largest city and urban area north of the Arctic Circle in Sápmi (following Murmansk). Most of Tromsø, including the city centre, is located on the small island of Tromsøya in the county of Troms, 350 kilometres (217 mi) north of the Arctic Circle. Substantial parts of the urban area are also situated on the mainland to the east, and on parts of Kvaløya—a large island to the west. Tromsøya is connected to the mainland by the Tromsø Bridge and the Tromsøysund Tunnel, and to the island of Kvaløya by the Sandnessund Bridge. The city is warmer than most other places located on the same latitude, due to the warming effect of the Gulf Stream.