Currently, the world's longest undersea section of a tunnel belongs to the Channel Tunnel, which has a 23.5-mile (37.9 kilometers) underwater section connecting England and France. Construction on the ...

The $20 trillion "Transatlantic Tunnel" construction that could connect the U.S. and the U.K. by rail has been branded a "high-risk" project by one of the world's leading megaproject experts.

A proposal to build a Transatlantic Tunnel between New York and London has resurfaced, and tech billionaire Elon Musk has thrown his company into the discussion. He believes he can slash the cost ...