Alton is a town in Belknap County, New Hampshire. Its population at the 2010 census was 5,250. Alton Bay, a long-time resort located beside Lake Winnipesaukee, is included within the town limits. The town is named after Alton, a small market town in Hampshire, England.
Historically, the most significant industry here was Rockwell Clough Company, established by William Rockwell Clough, inventor of the corkscrew. Currently, the primary industry is tourism. The steamer, Mount Washington, carries summer tourists between stops on the lake. Hiking to the summit of Mount Major, in Mount Major State Forest, which has an elevation of 1,780 feet above sea level, is popular here. It offers very scenic views of the lake and the surrounding area.