Antofagasta is a long and narrow city located south of the Mejillones Peninsula and north of the Cerro Coloso, north of Santiago. The city is bordered on the east by steep hills that are part of Chile's Cordillera de la Costa, and on the west by the Pacific Ocean.
Antofagasta lies in the Atacama Desert, which is among the Earth's driest regions. According to The Chilean Geological Magazine, annual rainfall in the city averages less than 4 mm, and there was a period of 40 years when no rain fell.
Mejillones is a small port 65 km to the north, on the northern part of Península de Mejillones. About 90 km north of Antofagasta is Hornitos, a beach that attracts both tourists and locals. Tocopilla is a coastal city 188 km north of Antofagasta. Calama, the second-largest city in the Antofagasta Region, is 213 km northeast of the regional capital. La Negra is a medium-sized industrial complex approximately 10 km south-east of Antofagasta, on the Pan-American Highway.
Antofagasta was founded on October 22, 1868 by Bolivian President Mariano Melgarejo to create a port that would provide an outlet for salpeter (nitrate) exports and establish control over an area where Chileans had settled and were smuggling this material. Antofagasta's original name was "la Chimba," though the area was previously known as Peñas Blancas (Spanish for "White Boulders"). It was part of the Litoral Province of Bolivia until February 14, 1879, when it was occupied by Chilean troops. This event marked the beginning of the War of the Pacific. Antofagasta is sometimes referred to as the Captive Province in Bolivia. The Bolivian government has made efforts to regain control of the city.
The commune of Antofagasta belongs to 2ª circunscripción (II Region of Antofagasta), which is represented in Senado by the senators Carlos Cantero (RN Renovation) and José Antonio Gómez (PRSD). Of equal way, the commune is part of distrito number 4, which is represented in Cámara de Diputados of Congreso Nacional by the deputies Manuel Rojas (UDI) and Pedro Araya (PDC)
Antofagasta's economic development has been based on extraction of raw materials. Primary extraction has shifted from guano to potassium nitrate (saltpeter) to copper. Antofagasta was formerly known as the main copper port of Chile, however, in recent years Mejillones have taken the leadership in copper transportation mainly due major infrastructure investment in that area (including a new port called "Megapuerto de Mejillones"). The city's economic mainstay is based on providing housing and services to the mining operations surrounding the city.
Antofagasta's industrial complex is north of the city. The city has a small agricultural zone in Quebrada La Chimba.
North of the city, along the seacoast, is a natural monument that features a large rock with a wave-created opening, called La Portada de Antofagasta ("The Doorway to Antofagasta").
An important railway, Ferrocarril de Antofagasta a Bolivia runs east to Bolivia, used to haul minerals over the high Andes. The history of the railway dates back to 1872 with the grant of a concession by the government of Bolivia to Melbourne Clarke & Co, the territory around Antofagasta being part of Bolivia at this date. The railway was organised as the Antofagasta Nitrate & Railway Company. Construction started in 1873, with the first section opening late in that year, motive power provided by mules. Steam locomotives were introduced in 1876, and by 1879 the railway had extended about 150km into the interior. War broke out in 1879 between Chile on one side, and Peru and Bolivia on the other. One of the causes of the war was an attempt by the Bolivian government to levy back taxes on the railway.
The line east was 2 foot 6 inch gauge, while the lines in Chile Littoral were meter gauge.
Although the public schools are distributed almost uniformly throughout the city, private schools operate mainly in the central and southern part of the city, where the wealthiest inhabitants reside.