Antioquia (Spanish pronunciation: [anˈtjokja] (listen)) or "Antioch", is one of the 32 departments of Colombia, located in the central Northwestern part of Colombia with a narrow section that borders the Caribbean Sea. Most of its territory is mountainous with some valleys, much of which is part of the Andes mountain range. Antioquia has been part of many territorial divisions of former countries created within the present-day territory of Colombia. Prior to adoption of the Colombian Constitution of 1886, Antioquia State had its own sovereign government. The department covers an area of 63,612 km2 (24,427 sq mi), and has a population of 5,819,358 (2006 estimate); 6.6 million (2010 estimate). Antioquia borders the Córdoba Department and the Caribbean Sea to the north; Chocó to the west; the departments of Bolivar, Santander, and Boyaca to the east; and the departments of Caldas and Risaralda to the south. Medellín is Antioquia's capital city, and the second-largest city in the country. Other important towns are Santa Fe de Antioquia, the old capital located on the Cauca River, and Puerto Berrío on the Magdalena.