Location: Tokyo Bay (东京湾)
Year built: 1966-1997
The Tokyo Bay Aqua-Line or Tokyo Wan Aqua-Line (東京湾 アクア ライン Tōkyō-wan Akuarain?) Is the combination of a bridge and a tunnel of Tokyo Bay in Japan. The gallery, which with a length of 5 km is the longest road tunnel subalveo of the world, is followed by a bridge length of 4.4 km.
The transition between the bridge and tunnel takes place on the artificial Umi hotaru (海 ほたる, en. Firefly of the sea).
In the gallery, twin cylinder, 60 meters below the water surface, runs the 409 national road with two lanes in each direction. The work connects the industrial area located south of Tokyo Kawasaki in Kanagawa Prefecture with Kisarazu in Chiba Prefecture on the Boso Peninsula.