La Paz, city, administrative capital of Bolivia, westcentral Bolivia. It is situated some 42 miles (68 km) southeast of Lake Titicaca. La Paz, which lies between 10,650 and 13,250 feet (3,250 and 4,100 metres) above sea level, is the world's highest national capital. Visitors, upon arrival, often find exertion difficult because of the rarefied atmosphere at those elevations.