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
Challenger Deep Challenger Deep The Challenger Deep is the deepest known point in the Earth's seabed hydrosphere, with a depth of by direct measurement from submersibles, and slightly more by sonar bathymetry. It is in the Pacific Ocean, at the southern end of the Mariana Trench near the Mariana Islands group. The Challenger Deep is a relatively small slot-shaped depression in the bottom of a considerably larger crescent-shaped oceanic trench, which itself is an unusually deep feature in the ocean floor. The Challenger Deep's bottom is about long and wide, with gently sloping sides. The closest land to the Challenger Deep is