Cochabamba (Quchapampa; Quchapampa) is a city and municipality in central Bolivia in a valley in the Andes mountain range. It is the capital of the Cochabamba Department and the fourth largest city in Bolivia, with a population of 630,587 according to the 2012 Bolivian census. Its name is from a compound of the Quechua words qucha "lake" and pampa, "open plain." Residents of the city and the surrounding areas are commonly referred to as cochalas or, more formally, cochabambinos. It is known as the "City of Eternal Spring" or "The Garden City" because of its spring-like temperatures all year round. It is also known as "La Llajta," which means "town" in Quechua. It is the largest urban center between the higher capital of La Paz and Santa Cruz de la Sierra in the tropical plains of the east. It sits south-west of the Tunari mountains, and north of the foothills of the Valle Alto. In antiquity, the area featured numerous lakes, which gave the city its name. Many of these lakes have since disappeared to urban development, but Coña Coña and Alalay lakes are extant examples. It has been a populated settlement since the Pre-Inca period, and is today an important cultural, educational, political, and commercial centre. The Cochabamba valley has been inhabited for thousands of years due to its fertile productive soils and mild climate. Archaeological evidence suggests that the initial inhabitants were of indigenous ethnic groups: Tiwanaku, Tupuraya, Mojocoya, Omereque, and Inca inhabited the valley at times before the Spanish arrived. The area got its name from Quechua Kochaj-pampa, as part of the Inca civilization. The area was conquered by Topa Inca Yupanqui (ruled 1471–1493). His son Huayna Capac turned Cochabamba into a large production enclave or state farm to serve the Incas. The local population was possibly depleted during the Inca conquest and Huayna Capac imported 14,000 people, called mitimas, to work the land. The principal crop was maize which could not be grown in much of the high and cold heartland of the Inca Empire.