Arctic Circle level, although in mountainous regions there is often no direct view of the true horizon. Only four million people live north of the Arctic Circle due to the severe climate; nonetheless, some areas have been settled for thousands of years by indigenous peoples, who today make up 10% of the region's population. Tens of thousands of years ago, waves of people migrated from eastern Siberia across the Bering Strait into North America to settle. The largest communities north of the Arctic Circle are situated in Russia, Norway and Sweden: Murmansk (population 307,257), Norilsk (175,365), Tromsø (71,295), Vorkuta (59,231) and Kiruna
Arctic policy of Russia of the Sea (UNCLOS), which allowed countries to make claims to extended continental shelves. In accordance with UNCLOS, Russia submitted a claim to an extended continental shelf beyond its 200-mile (320 km) exclusive economic zone on December 20, 2001, to the UN Commission on the Limits of the Continental Shelf (CLCS). Russia claimed that two underwater mountain chains - the Lomonosov and Mendeleev ridges - within the Russian sector of the Arctic were extensions of the Eurasian continent and thus part of the Russian continental shelf. The UN CLCS neither validated nor invalidated the claim but requested Russia to submit