Located in Temple and Peterborough, Miller State Park is the oldest state park in New Hampshire. Founded in 1891, the park has more than 530 acres that you can explore, which includes Pack Monadnock. The size of the park grew significantly due to donations from the state and local residents. Miller State Park opens every year around the middle of May and closes near the middle of November before the first snowfall. All residents over the age of 65 receive free admission to the park.