Puerto Rico and the Forts of Old San Juan

The Spanish forts in the city of Old San Juan have evolved in a surprisingly logical way from their sixteenth-century nucleus, remnants of which are still extant. Part of their construction also dates from the seventeenth and first half of the eighteenth centuries, but most of the massive fortifications seen today were built in the period from 1765 to 1800. They represent the best military thought of the time for defense against attack both by land and by sea.