Pets allowed
Allowed with Restrictions
Elevation Gain
208.00 ft (63.40 m)
Trail type
4.10 mi (6.60 km)
Please respect the outdoors by practicing Leave No Trace. Learn more about how to apply the principles of Leave No Trace on your next outdoor adventure here.

Hikers on the Tri-State Marker Trail will find a well-maintained forest path leading them on a geographical adventure.

Located in the southeastern corner of Pennsylvania, the 3,212 acre White Clay Creek Preserve borders Delaware’s White Clay Creek State Park. Some trails cross the state lines for hikers to enjoy both the preserve and the park of the same name.

The Tri-State Marker Trail offers even more geography interest than crossing state lines. Rated as more difficult hiking, this loop trail is hiking-only. It leads through mostly woodland areas in Pennsylvania until a small sign indicates the location of a Tri-State marker. It is at this spot that Pennsylvania, Maryland and Delaware meet. The 1849 stone marker is engraved on each of four sides with a single letter. Two sides have a P, and two sides have an M. There are no information signs explaining why Delaware is not represented on the Tri-state marker.

However, along the trail there are clear markers indicating when hikers are crossing the state line into Delaware, and when they return into Pennsylvania. The trail has wooden bridges at small stream crossings. It does not have any amenities, but offers benches placed periodically along the trail. One bench bears a small engraved plate honoring the memory of the creator of the trail, Wendel Cassel, a master trail builder.

The trail offers another interesting geographical stop with a short out-and-back side excursion. Hikers who choose to take the extra trail before continuing the loop back to the parking area, will be rewarded with the opportunity to see a tall monument marking the southern-most point where Pennsylvania’s state boundary line meets Delaware and begins an arc-shaped border. Known as the Arc Corner Monument, the 1892 marker is engraved, “Field work executed by the United States Coast and Geodetic Survey.” One side is marked Pennsylvania, another side is marked Delaware.

Logistics + Planning

Preferable season(s)




Parking Pass


Open Year-round



Interesting geographical and historical sites. Hike in three states along one trail.


No information signs about the markers.

Trailhead Elevation

155.00 ft (47.24 m)

Highest point

242.00 ft (73.76 m)


Historically significant
Family friendly

Typically multi-day


Permit required




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