The Dyke Marsh Wildlife Preserve is located on the Virginia shore of the Potomac River just South of Old Town, Alexandria. 

From Old Town, take Washington Street South toward Mt. Vernon. Washington Street turns into the George Washington Memorial Parkway. One mile South of Old Town, look for signs announcing the marsh and the Belle Haven Picnic Area and Marina. Turn left into the park. 

From the beltway (I-495), take Route 1 South exit, staying in the right lane.  From the right lane, follow the sign for the left turn onto Fort Hunt Road.  From Fort Hunt Road, turn left on Belle Haven Road and follow it until it ends at the GWMP. Turn right onto the GWMP and take the first left into the park.

There are restrooms and parking at Belle Haven.  A path from the picnic area leads down to Dyke Marsh.