Fort Loudoun was the largest fort in colonial Virginia when Washington built it between 1756 and 1758, intended to anchor the defense of the Shenandoah Valley against French-allied raids from the Ohio Country. Washington was 24 years old when he began the project, and he threw himself into the work with characteristic energy and frustration: the Virginia colonial government consistently underfunded the effort, and he found himself unable to conscript sufficient labor or obtain adequate materials. The fort was never attacked in any significant action, and its military utility remained untested.
Today almost nothing remains of the original structure above ground. Archaeological excavations over the past several decades have located the foundations, and interpretive signage near the corner of Loudoun and Boscawen Streets marks the approximate location. The site is more interesting as a point of historical imagination than as a physical artifact — but standing roughly where the fort stood, at the northern end of what was then the Virginia frontier, gives some sense of what Washington was defending and why. The George Washington Office Museum, a short walk away, provides the contextual detail that the fort site itself cannot.