High Quality Content by WIKIPEDIA articles! Argentina is subdivided into twenty-three provinces (Spanish: provincias, singular provincia) and one autonomous city (Ciudad autónoma de Buenos Aires, informally the Capital Federal). The city and the provinces have their own constitutions, but exist under a federal system. Provinces are then divided into departments (Spanish: departamentos, singular departamento), except for Buenos Aires Province, which is divided into partidos. Even though there are provinces that belong to more than one region, they are shown here within the most representative region. In the Tucumán province, the smallest of Argentina, coexist three regions: the Pampas to the south, Gran Chaco to the northeast, and Argentine Northwest.