Nanjemoy is within the Washington, D.C., metropolitan area, approximately 25 miles (40 km) south of the Capital Beltway (Interstates 95 and 495).

The Nanjemoy area is becoming increasingly popular with Washington-area commuters, particularly those working in nearby Indian Head or Fort Washington in Maryland or in Alexandria, Virginia.

The settlement lends its name to the Nanjemoy Formation, which outcrops on the nearby shores of the Potomac River.

[2] The sunken hulls of dozens of the ships still are visible at low tide at Mallows Bay, and they are regarded as the "largest shipwreck fleet in the Western Hemisphere.

The Nanjemoy area, on the Atlantic Coastal Plain, includes the largest great blue heron (Ardea herodias) rookery in the Eastern United States north of Florida, now a preserve owned and managed by The Nature Conservancy.

It offers trails, a boardwalk through a freshwater tidal marsh, a pier, a pavilion, a laboratory building, and several cabins for use by school groups.

[12] Hunting and fishing have long been popular in the relatively undeveloped Nanjemoy area, and many miles of remote hiking trails are available.