Fort Runyon

Fort Runyon was a five-sided earthwork fortification built south of Washington during the Civil War to control access via the Columbia Turnpike and the Alexandria and Loudon Railroad. The structure had a perimeter of approximately 1500 yards and contained various artillery positions to prevent enemy approaches.

The Union Army built Fort Runyon in 1861 after Virginia seceded, making it the largest fort in Washington's defensive system. The fort played a key role in securing the southern approach to the Long Bridge and thus to the capital.

The fort was built by soldiers from multiple Union states working together to defend the southern approach. This cooperation between regiments from different states showed the united strength of the North during the war.

A historical marker in Arlington County today indicates where the fort once stood, now intersected by Interstate 395 near the Pentagon. Visitors can view this marker from the roadside, and the exact location is best found using a map or navigation app.

The fort required more than 2000 personnel to defend its position, including about 300 artillerymen stationed there around the clock. This large garrison shows how strategically important this location was for protecting Washington.

Location: Arlington County

Inception: 1861

Part of: Civil War defenses of Washington, D.C.

GPS coordinates: 38.86528,-77.05167

Latest update: December 13, 2025 12:42