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1.
Strait of Messina: Sicily to the Italian mainland
There have been plans, however.
2.
Øresund: Zealand (Denmark) to the Swedish mainland
A combination of a bridge and a tunnel opened in 2000.
3.
Cook Strait: the North Island to the South Island (New Zealand)
4.
Dardanelles: the Gallipoli peninsula to the Troad peninsula (Turkey)
The 1915 Çanakkale bridge opened only in March 2022.
6.
The English Channel: Great Britain to the French mainland
The Channel Tunnel opened in 1994.
7.
Strait of Bali: Bali to Java (Indonesia)
8.
The Solent: Isle of Wight to Great Britain
9.
Strait of Gibraltar: Spain to Morocco
10.
Vancouver Island to the Canadian mainland
11.
Bahrain to the Saudi Arabian mainland
The King Fahd Causeway opened in 1986.
12.
Strait of Kerch: the Crimea (Ukraine, occupied by Russia) to the Taman peninsula (Russia)
The Soviets built a bridge in 1944, but it was destroyed in 1945 by ice sheets. The new bridge opened in 2020.
13.
Bosporus: the Çatalya peninsula to the Kocaeli peninsula (Turkey)
There are two tunnels and three bridges. The first opened in 1973.
14.
Tsugaru Strait: Hokkaido to Honshu (Japan)
15.
Kanmon Straits: Kyushu to Honshu (Japan)
The Kanmon Bridge was opened in 1973.