Colombia is the only South American country with both Caribbean and Pacific coastlines. The fourth-largest country in South America, it has a total area of 1,138,910 sq km (439,736 sq mi), including insular possessions, and extends 1,700 km (1,060 mi) NNW – SSE and 1,210 km (750 mi) NNE – SSW . Comparatively, the area occupied by Colombia is slightly less than three times the size of the state of Montana. Bordered on the N by the Caribbean Sea, on the NE by Venezuela, on the SE by Brazil, on the SW by Peru and Ecuador, on the W by the Pacific Ocean, and on the NW by Panama, the Colombian mainland is located entirely within the tropics. Its total boundary length is 6,004 km (3,731 mi). Its coastlines extend 3,208 km (1,993 mi). Also held by the Republic of Colombia (though claimed by Nicaragua) are the archipelago of San Andrés and Providencia in the Caribbean Sea, about 190 km (120 mi) off the coast of Nicaragua, and the islands of Malpelo, Gorgona, and Gorgonilla in the Pacific Ocean. Colombia also holds the uninhabited Caribbean islands of Quita Sueño Bank, Roncador Cay, and Serrana Bank, to which the US renounced all rights under the Treaty of Quita Sueño, ratified by the US Senate in July 1981; Nicaragua also disputes this claim. Colombia has a dispute with Venezuela over maritime rights in the Gulf of Venezuela. Negotiations have been going on unsuccessfully since 1970, and in August 1987, a Colombian naval vessel entered the disputed region in an apparent attempt to make Venezuela more responsive.
Colombia's capital city, Bogotá is located in the center of the country.