And, perhaps just as interesting, the answer for Everest’s growth is down at ground level — specifically the Arun River north of the mountain. Thousands of years ago, its course of flow was changed due to erosion, and the Arun connected with its lower reach and became part of the nearby Kosi River system.

Mount Everest or Sagarmatha (top), highest peak in the world with an altitude of 8.848 metres (29.028 ft) is seen in this aerial view next to 6.812 metres (22.349 feet) high Mount Ama Dablam (bottom R) April 22,