Contests National Park Photo Contest Winners – 2021 Birds hitching a ride on a bison’s back in Lamar Valley in Yellowstone National Park Hitching a ride in Lamar Valley in Yellowstone National Park Share this Facebook Icon Twitter Icon Email Icon Join National Park Trips Create a personalized feed and bookmark your favorites. Join for free Already have an account? Sign In Join National Park Trips Create a personalized feed and bookmark your favorites. Join for free Already have an account? Sign In Photo: Cynthia Murphy