Mason Neck National Wildlife Refuge is located about 18 miles south of Washington D.C. From the north: take I-95 south to exit 163 (Lorton). Turn left on Lorton, right on Armistead Rd, and then right (south) on RT 1. Go to light at top of the hill and turn left on Gunston Rd. (242) and go about 4 miles. The refuge shares a common entrance (High Pt. rd.) with the Mason Neck State Park. From the south: take I-95 north to exit 161 (Rt 1, Ft. Belvoir), go north on Rt 1, turn right on Gunston Rd, go about 4 miles to refuge entrance.