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Scenes of summer from Yellowstone National Park

As summer begins, tourists are flocking to Yellowstone. Last year alone, the nation's first national park recorded over 3.6 million people.

Jim Urquhart / Reuters

Tourists walk around the Grand Prismatic Spring, the largest in the United States and third largest in the world, in Yellowstone National Park, Wyoming, June 22.

Jim Urquhart / Reuters

A grizzly bear and her cub roam the Hayden Valley in Yellowstone National Park, Wyoming, June 24.

Jim Urquhart / Reuters

The Grand Prismatic Spring, the largest in the United States and third largest in the world, is seen in Yellowstone National Park, Wyoming, June 22.

Jim Urquhart / Reuters

Clepsydra Geyser erupts, nearly constantly, in the Fountain Paint Pot area in Yellowstone National Park, Wyoming, June 21.

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