Concord River

The Concord River is a 16.3-mile-long (26.2 km) tributary of the Merrimack River in eastern Massachusetts, United States. The river drains a small rural, suburban region northwest of Boston. As one of the most notable small rivers in U.S. history, it was the scene of an important early battle of the American Revolutionary War and was the subject of a 19th-century book by Henry David Thoreau.