DYK: More people have orbited the Earth than hiked the Grand Canyon from end to end http://on.natgeo.com/2nFgdLT

DYK: More people have orbited the Earth than hiked the Grand Canyon from end to end http://on.natgeo.com/2nFgdLT 

https://twitter.com/NatGeoTravel/status/849260338981851136