THE UNION MILL LAND BRIEF
Land in the
Northern Inner Piedmont setting.
Union Mill CDP has 9.99 square miles of land in Fairfax County. Its Census reference point is in Northern Inner Piedmont, within Piedmont.
The Piedmont is a belt of irregular plains and hills between the Appalachians and the coastal plain. A complex mixture of older rocks underlies its pine and hardwood woodland landscapes.
Regional context: Piedmont ↗ · Classification at the Census reference point
Union Mill and Fairfax County
Union Mill is associated with Fairfax County in the Census boundary data. Start with the parcel’s tax bill to match the property to that jurisdiction, then confirm which government handles its land use.
Union Mill by land and water
The Census records 0.1 square miles of water within Union Mill, or 1% of its total area. It is 2.8 percentage points lower than the 3.8% recorded for Fairfax County. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Union Mill CDP has 40.8 times the land area of nearby Clifton town (0.25 square miles). These areas describe boundaries, not comparable property prices.

