Located in Patapsco Valley State Park, one of Maryland’s largest and most heavily used parks, this hike features the millrace that supplied water for making power at an old mill that closed in 1972. The narrow path along the bank of the Patapsco makes a pleasant trail with great views of the river. Begin your hike at the parking lot of Trinity United Methodist Church walk to Rock Haven Avenue and walk through the gate onto a long-abandoned gravel road to start your hike on an excellent circuit hike on which you are unlikely to see another person.