Castro, town, southern Chile. It lies 45 miles (72 km) south of the town of Ancud, on the east coast of Chiloé Island.
Castro was founded in 1567 and regrew after being destroyed by an earthquake in 1837. Apart from being a port and agricultural centre (potatoes, wheat, livestock), it also has a timber industry and sawmills. Pop. (2002) 29,148; (2017) municipality, 43,807.