Black River County Park – Cooper Mill

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Hike from the old Cooper Mill through the Black River Gorge and a pine forest, with a side trip to the ruins of Kay’s Cottage.

7.2 miles, or variations below. Roots, minor rocks, and some moderately steep sections.

  • 1.4 miles – Just to the spillway and back (noted below).
  • 4.0 miles – Shorter version of this hike, only to Kay’s Cottage and back.
  • 3.8 miles – Black River Trail to Kay Environmental Center and back.
  • Nearby: Hacklebarney; Schooley’s Mountain.

Our two cents:

Along the river is especially stunning in fall. The loop can be done in either direction, but this way puts the most scenic – and harder – sections in the beginning when you’re fresher.

Requires a short bit of walking along Pottersville Road (little traffic).

Updated: 11/2020 – Re-hiked. Major route and description revision since formerly unmarked trails have been blazed. Interactive map updated. Photos added.

10/2020 – Page refreshed, not re-hiked. 11/2018 – Re-hiked the first section to the spillway only. Added fall photos. 11/3/17 – Updated map/park link. 7/11/14 – Re-hiked, route adjusted, GPX added.


Print ahead. The kiosk might have trail maps too.

Note: The trail names (Black River, Bamboo Brook) no longer seem to be referenced on trail maps but they are still on trail signs. They’ve been removed in the description but left in the overview. The Patriot’s Path tree+path marker is on some trails.


Hiking the Jersey HighlandsHike of the Week, and 60 Hikes Within 60 Miles: New York City have this route in the other direction, and without the side trip to Kay’s ruins.

50 Hikes in New Jersey has a different route; a shuttle option (or a 13.2 mile out-n-back) to Bamboo Brook. Hiking New Jersey has a similar route but the map diagram is outdated.

Parking: N40 46.698 W74 43.217

66 Route 24, Chester Township, NJ 07930. Large dirt lot adjacent to the Cooper Grist Mill.

Parking is also available at Kay’s Environmental Center which is passed on this route.


Portable toilets in the parking lot. The old bathroom building has been removed.

Hike Directions:

Overview: BLUE (Black River Trail) – GREEN – ORANGE – GREEN/ORANGE – GREEN – RED (Conifer Pass) – BLUE (Bamboo Brook) – BLUE (Black River Trail)

From the parking lot, walk towards the Mill.

Path and fence next to stone mill building

0.0 – Walk down the steps next to the mill.

Check out the water wheel at the base of the mill.

Cooper Mill stone building

Cross a small footbridge and follow BLUE.

River with bright yellow and orange foliage

View of the mill along BLUE.

Cooper Mill with a stream in front and surrounded by fall color.

The trail follows the Black River and passes a fenced-in area of the old Hacklebarney mine.

Hiker on path surrounded by yellow leaves
Black River flowing over rocks

BLUE is generally level but rooty as it follows the water.

Trail with bright yellow foliage

Continue on BLUE as it passes Kay’s Pond.

Kay's Pond

0.7 – The spillway at the end of Kay’s Pond:

Water flowing over a spillway

// Shorter option, 1.4 miles: Retrace the route back from here. //

Continue following BLUE along the Black River.

River with fall foliage around it

1.2 – Turn RIGHT to now follow GREEN at a marker post.

1.4 – Turn RIGHT to now follow ORANGE on a wide path. Markers might not be noticeable right away. [GREEN continues ahead].

Orange marker on a tree along a wide leaf covered path

Cross the Black River on a wooden bridge with views of the river on either side. Continue following ORANGE as it heads uphill.

Wooden bridge covered in leaves
Black River surrounded by fall foliage

The river will come into view, keep an eye out on the left for stone steps leading down to Kay’s Cottage.

1.8 – Take the steps downhill to the ruins of Kay’s Cottage next to a dam (Optional: Continue to the path’s end a little bit further down, past the cottage).

Kay's Cottage from on the steps above
Outside stone wall and steps

Inside the remains of Kay’s Cottage:

Stone archway

Black River and dam near Kay’s Cottage:

Black River
Dam at Kay's Cottage
Kay's Cottage dam on the Black River

When ready climb back up the stone steps and retrace the route to the bridge.

Old stone steps covered with wet leaves

2.1 – Just after crossing the bridge, turn RIGHT to now follow GREEN/ORANGE.

Green and orange marker on a tree

GREEN hugs the river on a sometimes narrow trail with rocks and roots. While not exactly challenging, it isn’t an easy or beginner trail in spots.

The gorge is very pretty with rushing water and cascades over rocks.

Rock covered with leaves and a river surrounded by fall foliage

2.2 – Now follow GREEN. [GREEN-ORANGE ends.] The trail heads down to the right to the area opposite of Kay’s Cottage.

Front of cottage with water spilling over a dam near stone steps

A pond was created in front of the cottage by damming the Black River.

Pond in front of stone cottage
Front of an old stone cottage

2.5 – Continue following GREEN as it veers to the RIGHT. (Greyed out markers are off on the left.)

Pass the remains of a chimney.

Remains of a stone chimney

2.7 – Turn RIGHT to now follow RED. [RED also goes straight. GREEN ends.]

// Shorter: Keep straight on RED to turn back to the main network of trails. There are multiple trails to get back to BLUE which leads to the parking lot. //

RED follows the Black River in a very pretty gorge.

Large leaf covered rock next to flowing river
River flowing over rocks surrounded by yellow leaves

Eventually RED veers away from the river and heads uphill. Continue through a section of pine forest and cross a small stream.

Pine forest

3.7 – Cross Pottersville Road.

4.0 – Large directional signs. Turn LEFT to start following BLUE.

[RED ends. BLUE also goes to the right, which leads to Bamboo Brook Educational Center]

4.7 – Back at Pottersville Road. Turn RIGHT and walk along the shoulder of the road until the driveway for Kay’s Environmental Center.

Country road

4.9 – Turn LEFT onto the driveway for Kay’s Environmental Center.

Kay’s Environmental Center sign

Walk down the paved park road.

Patriots Path marker next to paved road to Kay's Center

5.1 – Veer LEFT off of the pavement onto the grass. This is marked BLUE but was hard to spot.

Continue on BLUE by turning quick RIGHT at a post with ORANGE. Follow the wide straight path, past a marker with a #3.

Follow BLUE around the front of Kay’s Environmental Center and through the parking lot.

Kay’s Environmental Center

5.4 – Cross the parking lot, heading LEFT towards the “Black River Trail” sign and the “Patriot’s Path” post.

Black River Trail sign

Shortly, follow BLUE as it turns RIGHT. [Pass WHITE, might not notice it].

5.6 – Patriot’s Path sign with “1.6 miles to Cooper Gristmill”. Turn RIGHT to continue on BLUE. [YELLOW goes left].

Patriot's Path sign

6.0 – Turn RIGHT to continue on BLUE.

Shortly, pass GREEN on the left, retracing the route from earlier on BLUE back to the parking lot.

Hiked 10/24/20.
Hiked 11/4/18. Just  to the spillway and back, 1.6 m RT.
Hiked 7/6/14. Trail Blog: “Black River County Park – Kay’s Cottage, Conifer Pass, Bamboo Brook – from Chubb Park

Hiked: 4/28/12. Trail Blog: “Black River Park – Cooper Mill to Lamerson Road
Hiked: 10/31/10. Trail Blog: “Black River and Cooper Mill on Halloween
Hiked: 10/18/08. Trail Blog: “Black River in October” w/ B&T.
Hiked: 9/7/08. Trail Blog: “Black River from Cooper Mill to Willowbrook“; 14.8 miles
Hiked: 2/26/06. Trail Blog: “Black River and Cooper Mill in Winter