Last updated: February 11, 2021
Place
Seige Room
Historical/Interpretive Information/Exhibits, Wheelchair Accessible
The Castillo was originally built to act not only as a refuge for the townspeople but also as a military warehouse. The Spanish used the western casemates for food storage, and they would have looked much like the supply room. Other casemates were filled with military supplies such as gunpowder, hardware, ship repair materials, and as many as 20,000 cannonballs.
All of the stone casemates were constructed between 1738 and 1756, a time of almost constant warfare between Spain and England in the New World. The walls were raised to 35 feet during this remodeling, and these arched ceilings were constructed. Vaulted casemates disperse the weight of the structure throughout the supporting walls and foundation, so they are able to hold much more weight than a simple squared roof. This made these rooms "bomb proof" and allowed the Spanish to place more cannon on the gun deck above. When the casemates were finished, the Castillo was able to defend itself, the city, and all approaches to the city out to three and a half miles, the maximum range of the 16-, 18-, and 24-pounder cannon mounted along the fort's walls.