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
Northern Arctic Ecozone (CEC) Northern Arctic Ecozone (CEC) The Northern Arctic Ecozone, as defined by the Commission for Environmental Cooperation (CEC), is a Canadian terrestrial ecozone which includes most of the Canadian Arctic Archipelago, the northeast peninsula of Nunavut, and the northwestern tip of Quebec. Its marine borders are with the Arctic Archipelago Marine Ecozone, and it is adjacent to the mainland Southern Arctic Ecozone. Sparsely populated, it is home to 15,000 inhabitants, approximately 80% of whom are Inuit. The largest settlement is Iqaluit. The cold winters are very dark, typically having no daylight for weeks or even months north of the Arctic Circle.