Sourland Mountain Preserve – Hunterdon
Hopewell, NJ 08525

Overview of Selected Trail

The yellow and white diamond trails take one through the environmentally sensitive Sourland Mountain habitat. On the way one passes through boulder fields of diabase rock that are in the middle of unbroken forest. The headwaters of many small streams are either crossed by the trail or right beside the trail. The two trails together make one big loop with a smaller loop midway on the yellow diamond trail. The Blue trail takes you away from the main parking area and goes out to Ridge Road.

Trail Map
Full Desc
Flora & Fauna
  • Sourland Mountain Preserve – Hunterdon
  • Distance:

    2.3 miles if both yellow and white loop trails are hiked. Allow 45 minutes for Blue trail which leads to Ridge Road.


    45 minutes to several hours if both the yellow and white trails are hiked.


    Yellow diamonds marked “Trail” on the trees for the Yellow trail and white diamonds of the White trail. Please Note: The Blue trail branches off the Service Road trail and connects to Ridge Road. It climbs through the boulder area and crosses one of the creeks in the area. The creek crossing may be impassable during the wet season. This trail also uses a D&R Greenway easement. Please follow the established trail.

    Trail Usage:

    Walking/Hiking, Dogs permitted on leash


    Very gradual increase in elevation with a steeper climb at the end of the yellow trail. Overall it is a change of 80 feet.


    Easy – The trails can be muddy, so boots are recommended. After periods of rain trails are very muddy.


    A small gravel parking lot that will hold seven cars is available.


    Trails are open for use from dawn to dusk. No Parking after sunset. No rock climbing or horseback riding. Deer hunting by permit only in the northern part of the reservation in December to February. During hunting season visitors are asked to wear blaze orange or confine their visits to Sundays when hunting is prohibited. This is a fragile environment which is very sensitive to disturbance. Stay on the trails marked with yellow or white “trail” marked diamonds.


    Great views and wonderful boulder fields


    From Trenton: Take Route 31 North. Turn right onto Route 654 to Hopewell. In Hopewell turn left at the second light onto Greenwood Avenue. The reservation is in 2.8 miles on the right (you will pass Hillbilly Restaurant (a local landmark). The Sourland Mountain Reservation is 0.5 miles after the restaurant on the right. The entrance to the parking lot is by a mail box for 235 Rileyville Road. From the Flemington Area: Take Route 202/31 South from the Flemington Circle for five miles to the jughandle for Wertsville Road. Exit on Wertsville Road (Route 602) and use the traffic light to crossover Route 202/31. Continue on Wertsville Road for about 3.3 miles to Rileysville Road (Route 607). Turn right onto Rileyville Road and go about 1.7 miles. The park entrance is on the left and is marked by a Green Acres sign as well as a County Park sign. The entrance is shared by two other driveways, continue up the center driveway to the small parking area. Do not block the gated access road.   A small parking lot is available on Ridge Road. Proceed back to Rileyville Road and turn right. Make the first right onto Ridge Road. The lot will about ½ mile on your right. From Princeton: From Nassau Street, follow Route 206 South to Elm Road. Turn right onto Elm Road. At the first traffic light, turn left onto Rosedale Road and follow to the end. Turn right onto Carter Road (CR 569). When you pass through the traffic light at Cherry Valley Road, the name will change to Hopewell-Princeton Road. Continue through this traffic light to the end of the road at Broad Street. Turn left onto Broad Street. At the next traffic light turn right onto Greenwood Avenue. Stay on this road for 2.8 miles (you will pass Hillbilly Restaurant (a local landmark). The Sourland Mountain Reservation is 0.5 miles after the restaurant on the right. The entrance to the parking lot is by a mail box for 235 Rileyville Road.

  • This is one of the most environmentally sensitive, fragile areas in the state. Please stay on the trail as you enjoy the walk. Look for a beautiful pool of dark water by a large rounded boulder to the left of the gate at the start of the trail. As you walk this trail look for rivers of boulders amongst the trees. These are diabase rock which has weathered out of the bedrock of the mountain. This type of rock exhibits spheroidal weathering giving the rounded shape to many of the boulders. Just beyond the end of the small loop trail there is a sedge bog with a wood duck nesting box on an old tree. This is the head of the small stream you see exiting the bog. Look for large chestnut oaks and white oaks as the trail continues uphill. In the spring look for trillium and ferns under the trees and skunk cabbage by the small brooks. At the end of the yellow diamond trail, the white diamond trail descends the hill and loops back to the yellow diamond trail across more boulder fields and small streams.

  • The swampy woods and thin soil support Red maple, Ironwood (horn beam) and Tulip popular. Moving into the better drained areas, one will find Hickory, White ash and American beech. White oak and Chestnut oak are found about halfway up the trail. The younger woods show the competition for light in the tall straight trunks. Small sedge bogs can be found along the trail and skunk cabbage is in evidence by some of the small stream headwaters. The undergrowth includes trillium, ferns and spice bush.

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  • This reserve is maintained by the Hunterdon County Parks Department. Area non-profit organizations are aslo working to preserve contiguous land in the Sourlands.

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  • Photos

    Sourland Mountain Preserve – Hunterdon
    Sourland Mountain Preserve – Hunterdon
    Sourland Mountain Preserve – Hunterdon


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