Mount Monadnock, New Hampshire

This 3,165-foot-tall mountain is one of the most climbed mountains in the nation, with around 125,000 people a year (an average of 342.2 hikers per day), make the trek. On a peak summer or fall foliage day, the mountain swarms with hikers from around New England, but especially Boston, which is visible from the bald summit on a clear day.