The mountain that beats Everest

Everest, at 8,849 metres, is the tallest mountain above sea level. But measured from the centre of the Earth, the farthest summit is another one: Chimborazo, an Ecuadorian volcano of "only" 6,263 metres.

The trick lies in the planet's shape. Earth is not a perfect sphere: it spins, and that rotation flattens it at the poles and swells it at the equator. The equatorial bulge adds about twenty-one kilometres of extra radius.

Chimborazo sits almost exactly on the equator, so it starts with an advantage: its summit ends up about two kilometres farther from the Earth's centre than Everest's.

Put another way: whoever stands on top of Chimborazo is at the point of the surface closest to the stars. Everest may keep the fame; the record belongs to a volcano in Ecuador.