Cedar Run (Occoquan River tributary)

Cedar Run is a stream located in Northern Virginia, United States. It is a significant tributary of the Occoquan River. The stream originates in the Bull Run Mountains and flows generally southeast through Fauquier and Prince William counties before joining the Occoquan River.

Cedar Run's watershed is primarily rural and forested, with some areas of agricultural and residential land use. It plays an important role in the local ecosystem, providing habitat for various species of fish, insects, and wildlife.

The stream is known to be affected by stormwater runoff and nonpoint source pollution, impacting water quality. Conservation efforts are underway to protect and improve the health of the Cedar Run watershed. These efforts often include best management practices for agriculture and development, as well as stream restoration projects.

Historically, the Cedar Run area was the site of several significant events during the American Civil War, including the Battle of Cedar Run (also known as the Battle of Slaughter Mountain) in 1862, fought nearby its upper reaches.