Ten islands on the Potomac River:
- Columbia Island (District of Columbia)
- Cobb Island (Charles County, Md.)
- Chopawamsic Island (Prince William County, Va.)
- Rosilie Island (Prince George's County, Md.)
- Bear Island (Montgomery County, Md.)
- Van Deventer Island (Montgomery County, Md.)
- The Three Sisters (District of Columbia)
- Saint Clement's Island (St. Mary's County, Md.)
- Knott Island (Washington County, Md.)
- Cox Island (Frederick County, Md.)
Van Deventer Island is very close to where I live, a little more than a mile and a half as the crow flies. It's part of the McKee-Beshers Wildlife Management Area, and can be reached only by boat. Or you could swim there, I suppose; it's pretty close to the Virginia shore. Despite the island's proximity to Virginia, it is part of the State of Maryland, thanks to a pair of interstate compacts placing the whole of the river, from the Maryland shore all the way to the low water mark of the Virginia shore, in Maryland. There are a handful of Potomac islands considered part of Virginia for one reason or another, and the part of the river that was ceded to the Federal government to create the District of Columbia also contains a handful of islands, but aside from those all the others are in Maryland.
