the buut tunnel
The Brooklyn-Battery Tunnel is in New York City and at 9,117 feet (2,779 m) is the longest underwater tunnel in North America.
Yes, the Lincoln Tunnel (and the Holland Tunnel) run underneath the riverbed, not under the surface of the water and through the river itself. In other words, they do not run underwater, but under the bottom of the river.
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1938
The first such railroad tunnel, constructed for the Allegheny Portage Railroad in Pennsylvania, was completed in 1832
There is no 'who' - The 'what' - is the channel tunnel.
fungi
The second largest underwater tunnel in England is the Mersey Tunnel, which connects Liverpool with the Wirral Peninsula beneath the River Mersey. It is a vital transport link for the region, accommodating both road and pedestrian traffic.
Their 4 million liter shark tank has a 100 meter underwater tunnel.
Brooklyn Battery
Tsugaru Strait, Japan: 53,850 metres (33.5 miles)