Selden Island is a 408-acre island in the

Potomac River The Potomac River () is in the Mid-Atlantic (United States), Mid-Atlantic region of the United States and flows from the Potomac Highlands in West Virginia to Chesapeake Bay in Maryland. It is long,U.S. Geological Survey. National Hydrography D ...

, located about WNW of

Washington, D.C. Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with ...

, United States. It is about long and wide. Although it is located within

Montgomery County, Maryland Montgomery County is the most populous County (United States), county in the U.S. state of Maryland. As of the 2020 United States census, the county's population was 1,062,061, increasing by 9.3% from 2010. The county seat is Rockville, Maryland ...

, the only road access is via a bridge connecting it to the

Loudoun County, Virginia Loudoun County () is in the northern part of the Commonwealth of Virginia in the United States. In 2020, the census returned a population of 420,959, making it Virginia's third-most populous county. The county seat is Leesburg. Loudoun County ...

side of the river. Archaeological evidence indicates the island has been a site of human activity since the Early

Woodland period In the classification of :category:Archaeological cultures of North America, archaeological cultures of North America, the Woodland period of North American pre-Columbian cultures spanned a period from roughly 1000 BC to European contact i ...

, around 1000 BC. A characteristic type of

pottery Pottery is the process and the products of forming vessels and other objects with clay and other raw materials, which are fired at high temperatures to give them a hard and durable form. The place where such wares are made by a ''potter'' is al ...

known as Selden Island ware dates from this period. 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 The National Register of Historic Places (NRHP) is the Federal government of the United States, United States federal government's official United States National Register of Historic Places listings, list of sites, buildings, structures, Hist ...

in 1975. In 2002, following the diagnosis of two Loudoun County teenagers with

malaria Malaria is a Mosquito-borne disease, mosquito-borne infectious disease that affects vertebrates and ''Anopheles'' mosquitoes. Human malaria causes Signs and symptoms, symptoms that typically include fever, Fatigue (medical), fatigue, vomitin ...

, mosquitoes from the island were found to carry the ''

Plasmodium vivax ''Plasmodium vivax'' is a protozoal parasite and a human pathogen. This parasite is the most frequent and widely distributed cause of recurring malaria. Although it is less virulent than ''Plasmodium falciparum'', the deadliest of the five huma ...

'' malarial parasite. In 2004, Selden Island was purchased by the

Howard Hughes Medical Institute The Howard Hughes Medical Institute (HHMI) is an American non-profit medical research organization headquartered in Chevy Chase, Maryland with additional facilities in Ashburn, Virginia. It was founded in 1953 by Howard Hughes, an American busin ...

as an addition to the

Janelia Farm Research Campus Janelia Research Campus is a scientific research campus of the Howard Hughes Medical Institute that opened in October 2006. The campus is located in Loudoun County, Virginia, near the town of Ashburn. It is known for its scientific research and mo ...

. It was formerly leased as a sod farm.

References

{{authority control Archaeological sites in Montgomery County, Maryland Islands of the Potomac River River islands of Maryland Landforms of Montgomery County, Maryland