Take a tour of the world's happiest countries

With the release of the 2015 World Happiness Report, we're sharing what makes the top 15 happiest countries so great.

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Yosemite National Park in the United States Yosemite National Park in the United States (Photo: Mikhail Kolesnikov / Shutterstock)

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15. United States

Ranked No. 17 in 2013, the United States moved up two spots since the last time the report was published. With 318 million people and climbing, the U.S. is one of the most populated countries to make this list. With a vast National Parks system showcasing the country‚Äôs natural beauty, a passionate sports culture and cuisine which highlights comfort food, Americans have lots of reasons to wake up smiling.

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