Tim Fitzharris / Conifers and Lower Yellowstone Falls, Yellowstone River, Grand Canyon of Yellowstone, Yellowstone National Park, Wyoming

Jack Dykinga / Toroweap Overlook in sunrise light illuminating rim rocks with Colorado River far below, Grand Canyon National Park, Arizona, USA.

Jack Dykinga / Toroweap Overlook in sunset light illuminating rim rocks with Colorado River far below. Grand Canyon National Park, Arizona, USA.

Jeff Foott / Waterfall and river in canyon, Calf Creek Falls, Grand Staircase-Escalante National Monument, Utah

Jack Dykinga / Lupan Point, looking west into sunset. Grand Canyon National Park, Arizona, USA, August.

Tim Fitzharris / Clouds at sunset, Black Canyon of the Gunnison National Park, Colorado

Nick Garbutt / Sun beam at sun rise over the Grand Canyon of the Yellowstone, Yelllowstone National Park, Wyoming, USA. January 2016.

Nick Garbutt / Sun beam at sun rise over the Grand Canyon of the Yellowstone, Yelllowstone National Park, Wyoming, USA. January 2016

Dong Lei / Blue poppy (Meconopsis betonicifolia), Mount Namjagbarwa, Yarlung Zangbo Grand Canyon National Park, Tibet, China.

Dong Lei / Chinese lady slipper orchid flowers (Cypripedium tibeticum), Mount Namjagbarwa, Yarlung Zangbo Grand Canyon National Park, Tibet, China.

Dong Lei / Himalayan honeybee (Apis laboriosa) Mount Namjagbarwa, Yarlung Zangbo Grand Canyon National Park, Nyingchi Prefecture, Tibet, China. October.

Jack Dykinga / Cottonwood (Populus fremontii) in autumn, Long Canyon, Grand Staircase-Escalante National Monument, Utah, USA. October 2013.