Signal Hill
Also known as: Wilcoxen Signal Station; 44pw138
Why it's listed
Signal Hill is a wooded ridge near Manassas, Virginia, topped by the earthen remains of a Civil War fortification and signal station. The works cover a site about 1,200 feet long, with embrasured artillery emplacements, parapets and a surrounding trench; six of seven bastions survive. Its importance lies in communication rather than combat. Before the First Battle of Manassas, Confederate Captain Edwin Porter Alexander made the hill the central station for a chain of signal posts along the Bull Run line, using semaphore or wigwag signals. On the morning of the battle he spotted a Union column crossing Bull Run toward the Confederate left and sent warnings that allowed troops to be shifted in time. This was the first use of the semaphore system in warfare. Union forces used the hill afterward. Later owners protected the earthworks, and the city of Manassas began acquiring the land for a park in 1972. Two houses have damaged parts of the fort, but most of it remains intact.
Significance in brief: It served as headquarters for a network of Confederate signal stations during the First Battle of Manassas, where Captain Edwin Porter Alexander used semaphore (wigwag) signaling in warfare for the first time. His warning of the Union flanking column at Sudley Springs was credited with affecting the battle's outcome. The earthworks remain largely undisturbed.
Machine-generated summary. This summary was generated by a language model from the official nomination document and has not been reviewed line by line by an editor. It may contain errors. Check the source document before relying on any detail. Source: nomination document (PDF) · National Archives catalog entry. NRHP reference 89001062, listed August 8, 1989. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence medium).
Key facts
| Address | Signal Hill Rd. and Blooms Rd., Manassas |
|---|---|
| County | Prince William County |
| Listed | August 8, 1989 |
| Reference number | 89001062 |
| Resource type | Site |
| Period of significance | 1861-1865 |
| Criteria |
|
| Areas of significance | Military, Communications |
| Level of significance | National |
| Status (as stated in the nomination) | Wooded hilltop with six of seven original bastions surviving; one house has destroyed the southwest bastion and another has cut into the fort, and the trenches have seen metal detecting. Partly acquired by the city for a park starting in 1972. |
| Acreage | 5.9 |
| Coordinates | 38.75164, -77.43833 (NPS GIS) |
What listing means for this property
Sites (archaeological sites, battlefields, landscapes) are often listed with a restricted address to protect them from looting or disturbance. Listing is honorary for private owners; federal undertakings on or near the site go through Section 106 review, and state laws may protect burials and artefacts regardless of listing.
General information, not legal or tax advice. Rules change; confirm with your State Historic Preservation Office or a qualified adviser.
Sources and further reading
- National Park Service, National Register of Historic Places database (snapshot May 2026), reference 89001062.
- Nomination form (PDF, National Archives) — catalog entry
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.