Pica is a Chilean town and commune in Tamarugal Province, Tarapacá Region. Situated in the inland of the Atacama Desert on an oasis, Pica is famous for its small and unusually acidic limes known as Limón de Pica. The town has a communal hot spring with a surface temperature of 40 °C, which makes it a popular bath place in the middle of the desert. It has hotels and all basic services. The town lies four kilometers to the northeast of the oasis village of Matilla.

Puquios are ancient systems of subterranean aqueducts which allow water to be transported over long distances in hot dry climates without loss of much of the water to evaporation. Puquios are found in the coastal deserts of southern Peru, especially in the Nazca region, and northern Chile. Forty-three puquios in the Nazca region were still in use in the early 21st century and relied upon to bring fresh water for irrigation and domestic use into desert settlements. The origin and dating of the Nazca puquios is disputed, although some archaeologists have estimated that their construction began about 500 CE by indigenous people of the Nazca culture.