Top 5 Oldest Military Buildings on US Soil

A few days ago a friend asked by what was the oldest military building on US soil. I found a few places that matched his criteria. Castillo San Felipe del Morro, Fort Christian, Castillo de San Marcos, Blackbeard's Castle and Fort Niagara are the 5 oldest military building on US soil. Let's talk about all 5 of these places.

5. Fort Niagara: This fort was built by the French in 1678 CE in New York. The French lost the fort to the British in 1759 CE to the British in the French and Indian War. The fort stayed in British hands until 1783 CE, when it was ceded to the new nation of the United States. It fell out of use by the time WWI and WWII rolled around. It did serve was a POW camp for German soldiers. Today it serves as a base for the US Coast Guard and historic site.

4. Blackbeard's Castle: This watchtower was built in 1679 CE. It was built by the Danes on the island of St. Thomas in the US Virgin Islands. It was build to help protect the city of Charlotte Amalie. No one knows when the tower took the name of Blackbeard's Castle... but the name has stuck.

3. Castillo de San Marcos: Is a fort located in Florida. Its was built in 1672 CE by the Spanish to protect the Spanish city of St. Augustine. The British gained Florida in 1763 CE. The Spanish regained Florida in 1783 CE. Then the US gained the territory in 1819 CE. The military used the fort until 1933 CE. It has been a historic site ever since.

2. Fort Christian: The Danes built this fort to protect the island of St. Thomas in the US Virgin Islands in 1672 CE. The fort served as the government and defense headquarters on the island. The fort was turned over to US when the islands were sold to the US in 1917 CE. Today it is used as a museum.

1. Castillo de San Felipe del Morro: This fort was built by the Spanish in 1539 CE. The fort was built to protect the city of San Juan. The Spanish ruled Puerto Rico 1539 to 1898 CE. The fort survived many battles and wars. Most were against the French and British. The American took over the island and the fort in the Spanish-American War (1898). The US military retired the fort in 1961 CE and it became a historical site.

All of these buildings are great examples of military engineering from their time periods. All of these buildings are still around today and can be visited. I found pictures of all 5 sites online and added them to each section as I talked about them.