It borders the Chilean Arica y Parinacota Region to the north, Bolivia's Oruro Department and Potosí Department on the east, Chile's Antofagasta Region to the south and the Pacific Ocean to the west.

Much of the region was once the Tarapacá Province of Peru, which was annexed by Chile under the 1883 Treaty of Ancón at the close of the War of the Pacific.

The region was important economically as a site of intense saltpeter mining, before synthetic nitrate manufacturing became possible.

[4] The government of the region resides in the intendant, who is assigned by the president.

A marginal desert region can be found over 3,000 m (9,843 ft) above sea level, which sees milder temperatures and summer rains.