Round Hill and Weir Hill Loop

This easy route begins from roadside parking along Lincoln Road near its junction with Concord Road in Sudbury, MA. From the trailhead, head north and follow signs into the Sudbury Valley Trustees’ Round Hill property. At intersection G, turn left, then turn right at the next junction. Stay left at the next junction to cross Weir Hill Road and continue into the Sudbury unit of the Great Meadows National Wildlife Refuge. After crossing the road, the route continues as the Weir Hill Trail—stay left again for a short climb to the summit of Weir Hill. From there, descend toward the Sudbury River and circle around the refuge headquarters, passing through the parking area to reconnect with the trail. Continue on the trail around a small pond before beginning the return. On the way back, hikers can either retrace their steps or stay left for a brief climb to the hilltop of Round Hill, a glacial drumlin with wide views across the river’s floodplain. Expect wet or muddy conditions near the marsh, especially in spring or after rainfall. Interpretive signage and wildlife viewing opportunities add interest along the way. Dogs are not allowed within the refuge but are permitted on leash on town and Sudbury Valley Trustees lands outside the refuge boundary. The varied terrain and sequence of forest, hilltop, and floodplain make this route an engaging and well-rounded walk.