Tiwanaku is located on the Altiplano, near the southern beaches of Lake Titicaca, at an elevation of 3,850 metres, in the Province of Ingavi, Department of La Paz. Tiwanaku, the capital of a strong pre-Hispanic kingdom that ruled over most of the southern Andes and beyond, reached its zenith between 500 and 900 AD. Semi-underground Temple, Kalasasaya's Temple, Akapana's Pyramid, and Pumapumku's Pyramid Furthermore, structures like the Palace of Putuni and Kantatallita reflect the area's politicians and administrative authorities. Archaeological excavations were performed from 1978 through the 1990s by University of Chicago anthropologist Alan Kolata and his Bolivian counterpart, Oswaldo Rivera. Tiwanaku, often called Tiahuanaco or Tiwanacu, was a prominent pre-Columbian civilization noted for its remains near the southern coast of Lake Titicaca in Bolivia. The main Tiwanaku site was inscribed on the UNESCO World Heritage List in 2000.