The
municipalities of Puerto Rico number seventy-eight and they make up the smallest electoral division in
Puerto Rico. Each
municipality is led by a
mayor and divided into
barrios, though the latter are not vested with political authority. Geographically, a municipality has an urban core that consists of either a town or a city. Urban cores with a population of 50,000 or above are considered cities, while those under 50,000 inhabitants are termed towns.