The Eiksund tunnel is an undersea tunnel near Volda in Møre og Romsdal county in Norway. The tunnel, which joins the island of Hareidlandet with mainland Norway, serves the municipalities of Herøy, Sande, Ulstein, and Hareid, which together have approximately 22,000 inhabitants.
The tunnel is 7,765 m (25,476 ft) long and 287 m (942 ft) deep, which makes it the deepest undersea tunnel of its kind in the world. The tunnel was opened for public traffic in February 2008. The 405 m (1,329 ft) long Eiksund Bridge and the 1,160 m (3,806 ft) long Helgehorn Tunnel were built along with the tunnel. These three structures are a part of Riksvei 653, a county highway.
