Anyone with vertigo best look away now: Canadian space and defence company Thoth Technology has been granted a US patent for a “space elevator” that would reach a stomach-churning height of 20km above the ground.

Why, you might ask, would anybody want that? For “for wind-energy generation, communications and tourism” according to Thoth.

The elevator also offers a new way to access space, thus saving on rocket fuel. “Astronauts would ascend to 20 km by electrical elevator. From the top of the tower, space planes will launch in a single stage to orbit, returning to the top of the tower for refueling and reflight,” says Dr. Brendan Quine, the inventor.

Which sounds great. But frankly they can keep the tourism for themselves.