The concept of a tunnel connecting Britain and the United States has long been a visionary idea in the realm of futuristic infrastructure.

At an eye-watering price tag of around $19.8 trillion (£15.6 trillion), this project would be the ultimate expression of ambition, bridging the 3,400-mile gap between the two nations and solidifying the historic “special relationship” they share.

While the current flight from London to New York takes roughly eight hours, advocates of the tunnel dream of cutting these long-haul journeys down to mere “commutes,” making transatlantic travel a quick, everyday affair.

The idea, which first emerged more than a century ago, calls for an undersea passage stretching across parts of the Atlantic Ocean, some sections of which are several miles deep. To give a sense of scale, the Channel Tunnel, which connects England and France and is just 23.5 miles long, took six years to complete.

Various approaches have been suggested to make this Transatlantic Tunnel a reality, including placing it beneath the ocean floor, floating it at the surface, or even combining both methods. One particularly imaginative plan proposes a floating tunnel that would hover about 49 meters below the water, built from pre-fabricated segments and held in place by strong cables.

This groundbreaking concept envisions a system where trains could seamlessly travel across continents, bypassing the intense pressures of the deep ocean and avoiding maritime dangers. It’s widely believed that this system would be designed for trains rather than cars, as car trips would take several days and require additional infrastructure for drivers. According to the Mirror, Vactrains could, in theory, reach speeds up to 5,000mph.