The swamp is 21 miles (34 km) of braided stream stretching the length of Charles County and is a tributary of the Potomac River.

[2] It sits at an elevation of three feet (0.91 m) and 450 acres (180 ha)[2] of its southern end is protected as the Zekiah Swamp Natural Environment Area.

One of the original Thirteen Colonies, the Province of Maryland was established by Cecilius Calvert, 2nd Baron Baltimore as a haven for Roman Catholic Englishmen.

[6] A courthouse was built in 1674 and archaeologists believe they have found the location of a "summer house" constructed by colonial governor Charles Calvert, 3rd Baron Baltimore.

[6][7] After assassinating Abraham Lincoln in April 1865, John Wilkes Booth fled to southern Maryland, toward Zekiah Swamp.

[8] A black tobacco farmer guided Booth and his co-conspirator David Herold through the swamp to the home of a Confederate sympathizer, Samuel Cox.

Cox led Booth and Herold to Thomas A. Jones who helped them the rest of the way through the Zekiah Swamp and across the Potomac River to Virginia.

A tributary of the Potomac River, the swamp is 21 miles (34 km) of braided stream, stretching the length of Charles County.

It passes through two parcels of privately owned, but undeveloped land, to Zekiah Swamp Natural Environment Area where it empties into the Wicomico.

[2] Maryland is home to a wide array of ecological habitats, ranging from barrier islands and beaches, to saltwater estuaries, coastal plains and the Appalachian Mountains.