Hamlin is a town in Aroostook County, Maine, United States. It is located on the Canada–US border with a border crossing into Grand Falls, New Brunswick and is the closest continental location to Europe in the United States. Hamlin's northeastern corner is the closest point in the mainland United States to Western Europe, situated at a distance of 2,508 miles (4,018 km) from the closest point in Europe to the USA, Achill Head. The population was 166 at the 2020 census.