The Shawsheen River is a 22-mile-long river located in northeastern Massachusetts. It flows through several towns, including Andover, Billerica, and Wilmington, before joining the Merrimack River. The river is known for its scenic beauty and provides habitats for various wildlife species. Historically, the Shawsheen River played a significant role in the local economy, particularly during the industrial era when mills were established along its banks. Today, it is a popular spot for recreational activities such as fishing, kayaking, and hiking along its trails, contributing to the area's outdoor appeal.