The age of discovery is not over, hidden for all of human history, a 740 kilometers (460 mile) long canyon has been discovered below Greenland’s ice sheet. Using radar data from NASA’s Operation IceBridge and other airborne campaigns, scientists led by a team from the University of Bristol found the canyon runs from near the center of the island northward to the fjord of the Petermann Glacier.
It is the longest canyon on Earth, besting the 446 kilometers (277 miles) Grand Canyon in the United States and the previous number one; the 496 kilometer (308 mile) long Yarlung Tsangpo Grand Canyon in China.
Greenland seems to bowl inward with water thereby collected in the middle. But the melting water from the interior ice sheet seems to be draining to the sea instead of pooling in the middle. It is possibly drained via the Canyon, thereby explaining the lack of lakes under the ice sheet.