Bison walking on road, Yellowstone National Park, Wyoming, USA

Dead trees and mineral lake, Yellowstone National Park, Wyoming, USA

Landscape with steaming geysers at sunset, Yellowstone National Park, Wyoming, USA

Landscape with forested valley and mountains, West Glacier, Glacier National Park, Montana, USA

Bison crossing road, Yellowstone National Park, Canyon Village, Wyoming, USA

Young man 1acticing on slack line, Tuolumne Meadows, upper part of the Yosemite National Park, California, USA

Two rock climbers on portaledges on triple direct, El Capitan, overhead view, Yosemite Valley, California, USA

Woman looking up from portaledge on triple direct, El Capitan, high angle view, Yosemite Valley, California, USA

Sunset on Grand Canyon from south rim, Nevada, USA

Grand Canyon from south rim near the top of the Bright Angel trailhead in Grand Canyon Village, Nevada, USA

Tourist carpark in valley, Yellowstone National Park, Wyoming, USA