This would exceed the combined lengths of the two longest undersea tunnels on Earth, the Seikan tunnel and the Channel tunnel.
这将超过地球上两个最长的海底隧道青函隧道和英法隧道的长度总合。
2
The Tsugaru Strait separates Hokkaido from Honshu, although the two islands are connected by the underwater railway Seikan Tunnel.
津轻海峡连接了北海道和本州岛，同时青函海底隧道也将两个岛屿紧密相连。
3
The Gotthard tunnel will exceed the 53.8-kilometer Seikan rail tunnel linking the Japanese islands of Honshu and Hokkaido and the world's longest road tunnel, the 24.5-kilometer Laerdal in Norway.