city, capital of Santa Cruz provincia (province), extreme southern Argentina. It lies on the southern (right) bank of the estuary of the Gallegos River, inland from the Atlantic Ocean, about 40 miles (65 km) north of the Strait of Magellan.

Founded in 1885, it was named for Blasco Gallegos, one of Ferdinand Magellan's pilots, who is credited with discovering the river. Prehistoric cave paintings near the city are reminiscent of the Lascaux cave paintings in Dordogne, France.

Río Gallegos is the centre of the Patagonian sheep trade and exports frozen mutton, sheepskins, and gamulanes (leather coats). The deepwater port of Punta Loyola, at the mouth of the estuary of the Gallegos River, serves as the outlet for Argentina's bituminous coalfields at El Turbio, 130 miles (210 km) west; petroleum and natural-gas deposits to the north and south of Río Gallegos are exploited. The city also has a major Argentine air base. Pop. (2001) 79,144.