Monson is a town in Piscataquis County, Maine, United States. The population was 686 at the 2010 census. The town is located on Route 15 which is a somewhat major route north to the well known Moosehead Lake Region, to which Monson is sometimes considered a gateway. This route ultimately leads to the Canadian Province of Quebec.The town is well known in local and state history, but is minimally known elsewhere, although contributions by the town, and its location are notable. It is the last town located on the Appalachian Trail at the beginning of the 100-Mile Wilderness. It is not uncommon to see many hikers in town resting before their trip into the Wilderness, and several lodging places in town cater directly to these hikers.