San Felipe Castle is one of the old military fortresses guarding the Ferrol estuary. Located in the town of Ferrol, province of A Coruña, Galicia, Spain, it was built in the 16th century.
Facing this castle across the estuary stand La Palma Castle in the municipality of Mugardos and San Martín Castle. A heavy chain was once stretched across the sea between San Martín and San Felipe to block enemy ships from entering the estuary.
Construction began in 1557 under King Philip II, from whom the castle takes its name. Between 1731 and 1755, engineer Francisco Montaigú designed a series of reforms, including a hornwork, a moat and the main gateway.
In 1588, part of the Spanish Armada sought refuge in the Bay of Ferrol. English and French forces failed to take the town in 1594 and 1639 respectively.
On 25 August 1800, over one hundred ships and fifteen thousand men under Rear Admiral John Borlase Warren attempted to seize Ferrol during the Battle of Brión. Three waves of attack were repelled thanks to La Palma fortress. Napoleon celebrated the English defeat saying: "Thanks to the brave people of Ferrol."
The castle was purchased in 2000 by the Ferrol city council for 165 million pesetas.