Photo by @pedromcbride for @natgeo // My most challenging assignments seem to include traveling by foot. During the Bhutan’s Snowman Trek—a 230-mile walk along Bhutan’s Tibetan border, we walked 20 miles every day for a month. It's surprisingly more difficult mentally than physically, something I’ve been reminded of in my latest journey on foot, trekking the full length of the Grand Canyon this past year. #followme @pedromcbride for more images as I return to this rock realm this week. #chasingrivers #grandcanyon