The most sparsely populated state in the country — known for incredible wildlife and stunning natural vistas — is the nation's happiest, according to the latest Gallup-Healthways Well-Being Index data.

"The natural environment and year-round outdoor weather can both be helpful characteristics," Dan Witters, research director at the Gallup-Healthways Well-Being Index , told weather.com.

Hawaii, in the second-happiest spot, is also known for its natural beauty, and unlike Alaska, its hospitable year-round climate. This could help contribute to physical health, and in turn, well-being, Witters said.

"Hawaii, a year-round outdoor state, is in the top two for exercise [rates]," he said. "It does make it easier for people to get out and move naturally when you're in places with good weather."

The view might not hurt, either. "Emotional health is a good example [of this]," he said. "Daily happiness, daily smiling and laughter; daily stress and worry; clinical diagnoses of depression. What you see outside of you, outdoors, can and does lend a buoyancy to those kinds of emotional health metrics."

Interestingly, the state with the worst physical health ranked as the unhappiest in the nation overall. Click through the slideshow above to see which state is the saddest, and to find out how your state ranked.

Although physical health (whether driven by weather or not) isn't the only thing that matters. "It's also worth noting that we've got a lot of states in the Northern Plains that don't have year-round outdoor weather, sprawling mountains or an ocean around [them], and they have terrific well-being compared to the other states," Witters said.

A sense of economic opportunity, a feeling of social belonging and other factors also matter greatly, to be sure.

The ranking of states in order of self-reported well-being — from the highest to the lowest — is calculated using more than 176,000 interviews with American adults collected during the calendar year 2014. Each state is then ranked equally across Gallup's five key measures of well-being: sense of purpose, social well-being, financial well-being, community well-being and physical well-being.

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