The Grist Mill Trail at Patapsco Valley State Park is one of 1600 rail-trails supported by Rails-to-Trails Conservancy, a nonprofit organization that is working to create a nationwide network of trails from former rail lines and connecting corridors. Previously an unused railroad corridor, this "rail-trail" is now a great place to walk Fido in Ellicott City! The map below shows a parking area with convenient access to the Grist Mill Trail at Patapsco Valley State Park. Rails-to-Trails Conservancy has generously provided map data for this trail to Bring Fido for informational purposes only. For more detailed trail information, please visit TrailLink.com.