Tourists on boardwalk in silhouette, Grand Prismatic Spring, Midway Geyser Basin, Yellowstone National Park, UNESCO World Heritage Site, Wyoming, United States of America, North America

photography colour colour image color color image horizontal horizontal image outdoors outside day background people incidental people people in the background travel destination travel destinations travel tourist tourists holiday maker holiday makers on holiday grand prismatic spring midway geyser basin yellowstone national park unesco unesco world heritage site world heritage site wyoming usa us united states united states of america north america american north american north america national park scenics scenic scene scenes scenery tourism landmark landmarks famous well known well known hot spring geology geological geyser walkway physical geography topography geography geographical boardwalk steam tourist destination tourist destinations