What is "holmestrandsporten"

The Holmestrandsporten Tunnel is a long double track railway tunnel under construction which runs through Holmestrandfjellet in Sande, Holmestrand and Re in Vestfold, Norway. Located on the Vestfold Line, the tunnel is being built as part of the double-track high-speed segment from Holm to Nykirke. The new Holmestrand Station will be built inside the mountain in the middle of the tunnel.