Los Angeles is irregularly shaped and covers a total area of 498.3 square miles (1,291 km2), comprising 469.1 square miles (1,215 km2) of land and 29.2 square miles (76 km2) of water. The city extends for 44 miles (71 km) longitudinally and for 29 miles (47 km) latitudinally. The perimeter of the city is 342 miles (550 km). It is the only major city in the United States bisected by a mountain range.
Los Angeles is both flat and hilly. The highest point in the city is 5,080 ft (1,550 m) Mount Lukens, located at the northeastern end of the San Fernando Valley. The hilly parts of Los Angeles include the entire Santa Monica Mountains which stretch from Downtown to the Pacific Ocean, the Mt. Washington area north of Downtown, eastern parts such as Boyle Heights, the Crenshaw district around the Baldwin Hills, and the San Pedro district.
The Los Angeles River, a major river that is largely seasonal, is the primary drainage channel. It was straightened and lined in concrete by the Army Corps of Engineers for almost its entire length to act as a flood control channel. The river begins in the Canoga Park district of the city and flows east from the San Fernando Valley along the north edge of the Santa Monica Mountains as they diminish, then south through the city center, then through nearby Vernon on its way to its mouth in the Port of Long Beach at the Pacific Ocean.