It might have ended almost 150 years ago, but the American Civil War still rages inside a small wooden house in Culpeper, Virginia.

Known locally as the Graffiti House, it is thought to have served as a Confederate field hospital during the 1863 Battle of Brandy Station, one of the biggest conflicts between Confederate and Unionist forces. Wounded soldiers used the building’s walls as their canvas, leaving doodles, messages, signatures and regimental details to mark their temporary presence.

The first examples of the graffiti were discovered during renovations in 1993. Since then, conservators have uncovered eye-catching drawings of horses, women and soldiers, long hidden beneath layers of paint and wallpaper. More graffiti was found earlier this year, making the town an excellent spot to commemorate this year’s 150th anniversary of the start of the Civil War.

As I wander through the small, graffiti-covered rooms on the building’s second floor, it is easy to visualise wounded soldiers killing time with their sooty charcoal sketches. Around 32 of these soldiers have been identified via their graffiti, with some tags now accompanied by photographs of their authors, lending an eerie personal touch to the place.

More historic American graffiti

Chimney Rock National Historic Site, Nebraska
Pioneers migrating west carved their names on Chimney Rock, a 37m-high sandstone spire on the Oregon Trail. In the visitor’s centre, take a look at preserved graffiti and leave your own message for future travellers.

V-Bar-V Heritage Site, Arizona
Turtles and cranes, frisky humans and a rare female shaman are just a few of the 1,000 ancient Sinaguan petroglyphs on view at this fascinating site 100 miles north of Phoenix.

Alcatraz Island, San Francisco Bay, California
Native American activists left the phrase “Red Power” in graffiti on the exterior walls of America’s most famous prison during a 1969 to 1972 occupation of the island.

Angel Island Immigration Station, San Francisco Bay, California
Scores of poems are vivid reminders of the hardships faced by Asian immigrants detained here between 1910 and 1940 under the Chinese Exclusion Act of 1892.

Amy Balfour is an expert on California based in Los Angeles. She is co-writing Lonely Planet's latest USA guide.