The oldest masonry fort in the continental United States, the historic Castillo de San Marcos in St. Augustine was begun in 1672 and took more than 23 years to complete.
Authorized by the Queen of Spain to protect the nation's oldest permanently occupied settlement in the face of growing English and French settlements in the New World, the castillo was the most powerful fortress ever built by Spain to defend her coloney of La Florida.
Built of coquina, a unique natural rock formed of shell concretions and found in the St Augustine area, the massive fort was used as an active military post for more than 200 years and never fell to an enemy attack. Governor James Moore of South Carolina bombarded and laid siege to it in 1702. Governor James Oglethorpe of Georgia tried again in 1738, but also failed. Revolutionaries backed by the U.S. Army tried in 1812 but also failed to dent the walls of the massive Castillo de San Marcos.
The fort passed peacefully into the hands of the United States in 1821 and was renamed Fort Marion. It was a key post during the Second Seminole War (1835-1842) and the great Seminole leader Osceola was confined there briefly after he was taken prisoner while negotiating under a white flag.
Both Union and Confederate forces occupied the fort at different times during the Civil War and it was used as a prison for Apache, Kiowa, Comanche and other Indians during the years after the war. In 1898, 200 men were housed there after they tried to desert during the Spanish American War.
Fort Marion was declared a national monument in 1933 and its original name was restored by the U.S. Congress in 1942. Now the Castillo de San Marcos National Monument, it is open to the public daily. To learn more, please visit www.exploresouthernhistory.com/castillodesanmarcos1.