DC's Civil War Earthworks

In military terms, earthworks refer to fortifications constructed from dirt. Dirt is a very inexpensive resource, and when used in massive amounts it is the basis for a very strong and intimidating structure.

Although many cultures used earthen fortifications, the Civil War fortifications were based on the European model of the 17th and 18th centuries. Professor Dennis Hart Mahan of the United States Military Academy at West Point, New York, was the leading authority of fortification engineering. He based his book, A Treatise of Field Fortifications (published in 1836 and revised in 1852 and 1860) on the European prototypes. Major General John G. Barnard was tasked with the complex task of overseeing the design and construction of the Defenses of Washington using Mahan’s principles.

Each of the forts built to protect the nation’s capital was unique, while following a standard procedure for construction. By the time a fort was completed it was composed of walls that were made of dirt shoveled into berms. The rampart*, was lined with fallen trees. Inside the fort, the bombproofs*, were lined with wood. Guns peeked through embrasures*, cutting the top of the parapet*. A steep slope led down to a dry moat*. Beyond the ditch was abatis* that pointed outward. The abatis, which lay around the perimeter of the forts and batteries, formed a barricade much like modern barbed wire today.

*Definitions:

• Rampart- interior slope
• Bombproofs – earth covered rooms that shelter gun crews and officers
• Embrasures – notches cut in the top of fort walls
• Parapet – fort walls
• Abatis – a barricade of fallen trees
• Moat - a deep, broad trench surrounding a fortification

Duration:

2 minutes, 5 seconds

An overview of the Civil War Defenses of Washington, the roles of Fort Stevens and other forts in the Civil War, and how park visitors can experience these places today.