Tiwanaku Pre-Columbian archaeological site, located near the southern shores of Lake Titicaca in Bolivia. Situated at an altitude of 3,850 metres, the site is over 2000 years old. It started as a small settlement and later developed into a planned city between 400 CE and 900 CE. This city served as the spiritual and political center of the Tiwanaku Culture. At its peak around 800 CE, the population of the city was estimated to be between 10,000 and 20,000 people.