THE MASON COUNTY LAND BRIEF
Land in the
Central Puget Lowland setting.
Mason County has 959.6 square miles of land in Washington. 6 mapped landscape regions meet across Mason County: Central Puget Lowland, Volcanics, Low Olympics, among others.
A glacial lowland surrounds Puget Sound with islands, bays, peninsulas and rolling terrain. Moraines, outwash plains and river terraces create a varied setting beneath the region's maritime climate.
Regional context: Puget Lowland ↗ · Regional mapping across the county footprint
Where the landscape changes
Mason County intersects 6 mapped regional units. The largest mapped shares are:
- Central Puget Lowland59.2%
- Volcanics29.9%
- Low Olympics5.3%
- High Olympics2.5%
- Willapa Hills2.2%
Coast Range in Mason County
Pacific-facing coastal mountains support moisture-loving conifers, with marine terraces, dunes and beaches along the ocean edge. Inland slopes and the immediate coast have different vegetation patterns.
Read the regional source ↗North Cascades in Mason County
Rugged high mountains and glacial terrain span a strong west-to-east climate transition. Wetter maritime forests to the west contrast with drier inland conditions on the eastern side.
Read the regional source ↗Finding your parcel within Mason County
The atlas lists 7 cities, towns, townships, and Census communities associated with Mason County, including Belfair, Skokomish, Shelton. The list includes overlapping geography types and does not divide the county into exclusive service areas.
Mason County by land and water
The Census records 91.5 square miles of water within Mason County, or 8.7% of its total area. That share is close to Mason County’s 8.7%. This is geographic context; waterfront status and usable land must be checked at the parcel.
For scale, Mason County has 143.9 times the land area of nearby Skokomish CDP (6.67 square miles). These areas describe boundaries, not comparable property prices.
The Census boundary meets Grays Harbor County, Jefferson County, Kitsap County, Pierce County, Thurston County within Washington. A tract near one of these lines should be matched to the county identifier on its own records.

