Merkle Wildlife Sanctuary

Critical Area Driving TourCritical Area Driving Tour

The 4.3 mile Chesapeake Bay Critical Area Driving Tour (CADT) is open for self-guided driving tours on Sundays from 10 a.m.-3 p.m. year round. The tour starts at Patuxent River Park and continues into Merkle Wildlife NRMA, crossing the Mattaponi Creek. To access the Critical Area Driving Tour: take Croom Airport Road, off Croom Road to Patuxent River Park.

The 2-mile portion of the tour located within Merkle Wildlife is open for hiking, biking, driving, and horseback riding daily.

​Chesapeake Bay Critical Area Driving Tour​​


Patuxent River Park
16000 Croom Airport Road
Upper Marlboro, MD 20772
Prince George's County

Merkle Wildlife Sanctuary and Visitor Center
11704 Fenno Road
Upper Marlboro, MD 20772
Prince George's County

Access The driving tour begins at the entrance to the Jug Bay Natural Area of the Patuxent River Park and extends into the Merkle Wildlife Sanctuary. This is a one-way drive.
Distance 4.3 miles
Hazards/Restrictions The Chesapeake Bay Critical Area Driving Tour is available for driving only on Sundays from 10 a.m. to 3 p.m. You may only leave your car at designated areas.
Potable Water Water and restrooms are available at the visitors centers located at each end of the drive.
Natural Features This drive winds its way along the shore of the Patuxent River. It passes through natural woodlands and both tidal and non-tidal marshes. Birds and reptiles remain plentiful and large flocks of Canada geese may be seen during migration seasons.
Other Amenities There are visitors centers at both Patuxent River Park and Merkle Wildlife. Many miles of walking trails are within both parks and Patuxent River Park has biking and equestrian trails. Canoes are available for rent at Patuxent River Park.
Other Points of Interest The Patuxent River, Observation Tower, Board Walk, Lookout Creek Trail. The Duval Tool collection is located in Patuxent River Park.
Fees or Permits The Critical Area Driving Tour is free.
Description This short drive is through land that was designated as “critical” to the health and protection of the Patuxent River and ultimately the health of the Chesapeake Bay. The drive takes you through woods, over non-tidal and tidal marshes and through open farm fields, giving an intimate feel of what the ecosystem has to offer.

A 40 foot observation tower exists on the Merkle Wildlife portion of the drive, providing a spectacular overlook of the Patuxent River.


Merkle Wildlife Sanctuary homepage​