| Furnace Mountain | |
| Elevation: | 891feet |
| Prominence: | 491feet |
| Range: | Blue Ridge Mountains |
| Parent Peak: | Catoctin Mountain |
| Location: | Loudoun County, Virginia, U.S. |
| Map: | Virginia |
| Label Position: | bottom |
| Map Size: | 300 |
| Coordinates: | 39.27°N -77.55°W |
| Coordinates Ref: | [1] |
Furnace Mountain is the tallest peak of Catoctin Mountain in Loudoun County, Virginia. It rises steeply from the southern banks of the Potomac River across from Point of Rocks, Maryland and continues southward for 1miles, reaching an elevation of 891feet before falling to a gap between it and an unnamed peak of 800feet. Its name arises from the iron furnaces located at its base, which operated from the 1790s to the 1870s. The furnaces were used to process iron ore mined from the mountain, much of which was used to build the burgeoning city of Washington D.C.