 USGS Map of Selden Island | |
  Selden Island Selden Island (Maryland) | |
| Geography | |
|---|---|
| Location | Potomac River |
| Coordinates | 39°04′31″N 77°27′10″W / 39.07528°N 77.45278°W |
| Area | 408 acres (165 ha) |
| Length | 4.0 km (2.49 mi) |
| Width | 0.3–0.5 km (0.19–0.31 mi) |
| Highest elevation | 65 m (213 ft) |
| Administration | |
United States | |
| State | Maryland |
| County | Montgomery |
| Demographics | |
| Population | 0 (2022) |
Selden Island is a 408-acre island in the Potomac River, located about 32 km (20 mi) WNW of Washington, DC. It is about 4 km long and 0.4–0.5 km wide (2.5 x 1/4–1/3 miles). Although it is located within Montgomery County, Maryland, the only road access is via a bridge connecting it to the Loudoun County, Virginia side of the river.
Archaeological evidence indicates the island has been a site of human activity since the Early Woodland period, around 1000 BCE. A characteristic type of pottery known as Selden Island ware dates from this period.[1] It is also the site of a significant Late Woodland period settlement known as the Walker Prehistoric Village, which was added to the National Register of Historic Places in 1975.[2]
In 2002, following the diagnosis of two Loudoun County teenagers with malaria, mosquitoes from the island were found to carry the Plasmodium vivax malarial parasite.[3]
In 2004, Selden Island was purchased by the Howard Hughes Medical Institute as an addition to the Janelia Farm Research Campus.[4] It was formerly leased as a sod farm.