Achacachi is a town on the Altiplano plateau in the South American Andes in the La Paz Department in Bolivia. It is the capital of the Omasuyos Province.

The La Paz Department of Bolivia comprises 133,985 square kilometres (51,732 sq mi) with a 2012 census population of 2,706,359 inhabitants. It is situated at the western border of Bolivia, sharing Lake Titicaca with the neighboring Peru. It contains the Cordillera Real mountain range, which reaches altitudes of 6.6 kilometers (22,000 ft). Northeast of the Cordillera Real are the Yungas, the steep eastern slopes of the Andes Mountains that make the transition to the Amazon River basin to the northeast. The capital of the department is the city of La Paz and is the administrative city and seat of government/national capital of Bolivia.