The Seikan Tunnel Tappi Shakō Line (青函トンネル竜飛斜坑線, Seikan Tonneru Tappi Shakō-sen, "Seikan Tunnel Tappi Inclined Tunnel Line") is a Japanese funicular line in Sotogahama, Aomori, operated by the Seikan Tunnel Museum. The 3 ft (914 mm) narrow gauge line descends from the museum near Cape Tappi (竜飛崎) into an underground station on the Seikan Tunnel, which is the longest railway tunnel in the world.