Fort Marion (Formerly Fort San Marco) was begun by the Spaniards in 1565, and required 190 years in building, slaves being compelled to do the work.
The thickest part of the fort walls is 40 ft. The structure covers five acres. It was bombarded in 1744 by Governor Oglethorpe of the Colony of Georgia. It is built of coquina and is said to be the best preserved specimen in the world of the military architecture of its time. It is the oldest fortification on the western continent. Its walls and watch towers remain intact but its guns are dismounted and the moat is dry. It is in all respects a castle built after the plan of those of the middle ages in Europe.
There are inner and outer barriers, the barbican, the draw bridge, portcullis, wicket and all appliances of such fortifications. In 1836 the terreplein of the north east bastion caved in, exposing a deep and dismal dungeon. Impelled by curiosity the U.S. Military Engineer descended into this dungeon, where to his surprise, he discovered the skeleton of a man and woman in iron cages bolted to the wall.
The Arch, Fort Marion, St. Augustine, Fla.
Encline used by Spaniards for transporting cannon from plaza to terreplein, steps being modern. Arch of great strength without a key-stone.