Colorado's mild winters let retirees take advantage of its parks, trails and Rocky Mountains all year round.
State residents are some of the happiest in the country, according to Bankrate, and have access to great health care.
Related: Should I bet it all on Buffett?
One downside: Colorado's cost of living is higher than in 29 other states. Housing in Denver is pretty pricey and is on the rise. The average home value jumped 15% in the last year to $293,300.
