Canyon Bigger Than Grand Canyon Found in Greenland

Under ice sheet

One of the biggest canyons in the world has been discovered buried beneath more than two miles of ice in Greenland.

The hidden canyon is up to half a mile deep, six miles wide and stretches for 466 miles beneath the country's giant ice sheet.

It is thought to have been carved out by a meandering river more than four million years ago – at a time before ice covered the area and humans were just beginning to evolve from primates.