MAIN PLAZA - LEVEL V - This upper courtyard was an important focal point for the troops that manned El Morro and in this square you can imagine daily drill inspections, formations, and the reading of the Orders of the Day. The vaulted rooms around the Plaza served as officers' quarters, storerooms for food, magazines, and cannon firing positions. Today you will find them full of museum displays, the restrooms, an audiovisual theater, and the museum bookstore. The well in the center provided access to underground cisterns which could hold 315,000 gallons of rain water collected from the surfaces of El Morro, enough for a year's supply if the garrison were under siege.