Atlantic Ocean Tunnel Atlantic Ocean Tunnel The Atlantic Ocean Tunnel () is an undersea tunnel that is part of Norwegian County Road 64 which connects Kristiansund Municipality to Averøy Municipality in Møre og Romsdal county, Norway. The eastern end of the tunnel is on Kirkelandet island in the town of Kristiansund and the western end of the tunnel is on the island of Averøya, just west of the village of Sveggen. The long tunnel runs beneath the Bremsnesfjorden, reaching a depth of , making it one of the deepest undersea tunnels in the world. Construction began in 2006, and the tunnel opened on
Arctic Ocean deepest point is Litke Deep in the Eurasian Basin, at . The two major basins are further subdivided by ridges into the Canada Basin (between Alaska/Canada and the Alpha Ridge), Makarov Basin (between the Alpha and Lomonosov Ridges), Amundsen Basin (between Lomonosov and Gakkel ridges), and Nansen Basin (between the Gakkel Ridge and the continental shelf that includes the Franz Josef Land). In large parts of the Arctic Ocean, the top layer (about ) is of lower salinity and lower temperature than the rest. It remains relatively stable, because the salinity effect on density is bigger than the temperature effect.