San Antonio is a Chilean port city, commune, and the capital of the San Antonio Province in the Valparaíso Region. It has become the main freight port in Chile, surpassing Valparaíso in the 21st century. San Antonio is also the hub of the fishing area that stretches along the Chilean coast from Rocas de Santo Domingo to Cartagena.
The city is situated on hills and coastal dunes, to the north of the Maipo River's mouth, and is divided by two estuaries: Arévalo to the north and El Sauce in the Llolleo section. It is located at 33°35′S and 71°37′W and borders Cartagena to the north, Melipilla and the Maipo River to the east, Santo Domingo and San Pedro to the south, and the Pacific Ocean to the west. It covers an area of 502.5 km2 (194 sq mi).
