In recent days, we've been sharing details from what VISIT DENVER describes as the Mile High City's most successful tourism year ever; visitor spending in 2013 topped $4 billion for the first time. First up were tourists' ten favorite shopping and entertainment centers, followed by the 21 cities and states that sent the most tourists to Colorado. Now come the agency's top fifteen biggest tourist attractions of 2013 -- and there are definitely some surprises, beginning with number fifteen. Count them all down below. Number 15: Denver Broncos Number 14: Butterfly Pavilion Number 13: Colorado Railroad Museum Continue to keep counting down Denver's top fifteen biggest tourist attractions of 2013. Number 12: Buffalo Bill's Museum & Grave Number 11: U.S. Mint Number 10: Downtown Aquarium Continue to keep counting down Denver's top fifteen biggest tourist attractions of 2013. Number 9: Elitch Gardens Theme & Water Park Number 8: Colorado Rockies Number 7: Denver Museum of Nature & Science Continue to keep counting down Denver's top fifteen biggest tourist attractions of 2013. Number 6: Denver Art Museum Number 5: Denver Botanic Gardens Number 4: Red Rocks Park & Amphitheatre Continue to keep counting down Denver's top fifteen biggest tourist attractions of 2013. Number 3: Coors Brewery Number 2: Colorado State Capitol Number 1: Denver Zoo

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More from our Things to Do archive circa August 2013: "Photos: Denver's best free attractions and tours, part one."

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