Yellowstone National Park is the flagship of the National Park Service and a favorite to millions of visitors each year..Bears in Yellowstone National Park. Yellowstone is one of the few places in the lower U.S. where you can see grizzly bears. Bears typically roam Yellowstone between March and November..SAVE! See TripAdvisor’s Yellowstone National Park, WY hotel deals and special prices on hotels all in one spot. Find the perfect hotel within your budget with reviews from real travelers..Yellowstone National Park is an American national park located in Wyoming, Montana, and Idaho.It was established by the U.S. Congress and signed into law by President Ulysses S. Grant on . Yellowstone was the first national park in the U.S. and is also widely held to be the first national park in the world. The park is known for its wildlife and its many geothermal features .