San Pedro Castle or Citadel

Also known as the "citadel of Jaca", it was built between the 16th and 17th centuries on the orders of King Philip II and restored in 1968. The engineer Spanochi followed the canons of military architecture derived from the use of artillery, and it is today the only fortress in the world in this style of construction still standing. It has a pentagonal floor plan with a bastion in the form of an arrow at each corner, and a moat that today serves as a resting place for deer. Its drawbridge leads onto the parade ground, around which are arranged the various barracks. One of them houses the Museum of Military Miniatures, where you can learn more about the castle's history through 32,000 lead soldiers.