Valdivian Fort System

The Fort System of Valdivia (Spanish: Sistema de fuertes de Valdivia) is a series of Spanish colonial fortifications at Corral Bay, Valdivia and Cruces River established to protect the city of Valdivia, in southern Chile. During the period of Spanish rule (1645–1820), it was one of the biggest systems of fortification in the Americas.^[1] It was also a major supply source for Spanish ships that crossed the Strait of Magellan.

Building of the fort system began in 1645 and was overhauled after the Seven Years' War (1756–1763) by the military engineers Juan Garland and Manuel Olaguer Feliú. Having been a first-rate fort system in Spanish America, in the 18th century it was overshadowed by the forts of Cartagena de Indias, Havana and Puerto Rico.^[2] The Valdivian Fort System was however still the main coastal fortification on Spanish America's Pacific coast.^[2]

During its existence the fort system has seen hostilities twice; first in 1670 when it dealt with a suspicious English expedition led by John Narborough and finally in 1820 when Chilean patriots led by Thomas Cochrane successfully captured it.^[3]