6927 Meter underwater tunnel connecting Daecheon Port and Wonsan-do in Boryeong-si, Chungcheongnam-do will open in the end of this year (2021).

It will be longest underwater tunnel in Korea and fifth longest in the world. Its budget 519 billion won. Related infrastructure Wonsananmyeon Bridge, which connects Wonsando and Yeongmok Port, Anmyeondo, Taean-gun, was completed in December 2019. The opening of the submarine tunnel will shorten the time from Daecheon to Yeongmok Port from 90 minutes to 10 minutes.

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