From 1762-1783, the Castillo was in the hands of the British. Having turned Florida over to Britain after the Seven Years' War (1754-1763), Spain made itself scarce for 20 years, until the British were in turn defeated in the American Revolutionary War (1775-1783), and Florida was returned to the loving arms of Imperial Spain.

Here we see a reproduction of a British bunk bed, in which four chummy soldiers would sleep. The British added second floors to some of the Castillo's casemates during their stay, so as to house more soldiers.