The fort at Blockhouse Point was one of three earth-and-wood structures built in the area to protect the Potomac fords and C&O Canal from Confederate raiders. Built in the winter of 1862 by soldiers from the 19th Massachusetts Infantry, the fort took the form of a Greek cross. Although Blockhouse Point was located in Maryland, technically part of the Union, the area surrounding it was anything but hospitable. Montgomery County was a hotbed of secessionist activity. In addition, slavery was legal in Maryland, which gave the state an unappealing status to many northern soldiers. Scores of Northerners viewed the local populace with suspicion, wondering whether they were viewed as friends or enemies by the very people they were supposedly protecting.
Although no major engagements took place at the site, the fort itself became a casualty of war. In July of 1864, Union troops were withdrawn from Blockhouse Point to strengthen the defenses of Washington. Days later, Confederate cavalry under the command of Col. John S. Mosby destroyed the abandoned fortification during Jubal Early's raid on Washington City. The fort was never rebuilt. Archeological research has uncovered many artifacts from the location. Together with written records, they provide us with an intimate glimpse into the lives of the Union soldiers stationed at Blockhouse Point 150 years ago.