Why were the forts of Old San Juan built?
San Juan Bay was a sheltered harbor that had high political and military value in the days of sailing ships. The easiest course to cross the Atlantic from Europe to the Americas was to go south to the coast of Africa; place your ship in the dependable trade winds and sail due west to the Caribbean. The trade winds, and wealth of the Caribbean islands in colonial times, made this harbor a target. El Morro was built to defend against sea attackers; later San Cristbal was built to protect against attack on San Juan by land.
