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The 3197 acre Sourland Mountain Preserve is county owned and administered by the Somerset County Park Commission. The Preserve provides passive recreational opportunities in an undisturbed natural setting.

Additional Information

The Somerset County chapter of JORBA was started in 2006 and included both Washington Valley Park and Sourland Mountain Preserve. The first year JORBA concentrated on fixing some major drainage problems that had built up over the years on existing trails, as well as establishing a strong working relationship with the Park Commission. We took full advantage of the plentiful rock supply Sourland is so well-known for and began honing our trail-armoring technique, a skill that we would reuse many times on future projects. We also completed a major re-route of a badly eroded connector trail. At the end of 2008, we added a half mile of new singletrack that connected Roaring Rocks directly to trail marker #6, by way of the former 3M quarry property, which had been recently purchased by the County. The opening of this trail was a significant accomplishment, and represented a major milestone in JORBA’s partnership with the Park Commission.

In early 2009, the good will earned in 2008 carried forward with the approval and opening of a significant section of new trail. JORBA (in partnership with the Park Commission) designed, planned, routed and constructed the 3 Amigos trail on the former 3M property. We added 1.3 miles of brand new technical singletrack, completing construction of the entire trail in only 1 day. Due to the high volume of summer rains, much of the remainder of 2009 was spent addressing problem wet areas on the low lying trail between posts #9 & #10. Crews relocated two boardwalks and armored over 100′ of muddy trail. Several minor trail re-routes were also incorporated to bypass altogether several problematic (muddy) areas.


  1. Red Square – (3 Amigos) The newest addition to the park, this trail starts at Roaring Rocks, snakes along the ridge through some stunning terrain, and ends on the gas pipeline that bisects the park. There is very little elevation gain/loss on 3 Amigos, but the natural rock features that were incorporated into the trail make it a very challenging trail for intermediate/experts. The 1.3 mile long trail was built in a single TM session with over 25 JORBA volunteers lending a hand.
  2. White Square – (Boulderama) This trail runs between posts #4 & #1 on the park trail map. The best flow is from #4 to #1. There are rocks the size of fists, basketballs, and small cars along Boulderama. Dense rock gardens will test your technical skills, and there are plenty of opportunities to jump, huck and otherwise get air under your tires. Boulderama is the main trail that most hikers take right out of the parking lot, so be prepared to yield the right of way. Since this runs at the top of the ridge and through rocks it has different characteristics than many of the lower-lying trails. The trail is primarily built on a rock base so it is a lower maintainance trail. JORBA involvement here is more general maintenance and small reroutes only where necessary.
  3. Red Circle – (Roaring Rocks Extension) This trail was built by JORBA in fall 2008, linking Roaring Rocks to the main trail network (by post #6 on the trail map). JORBA teamed up with some local bouldering enthusiasts to construct the trail. In addition to providing some unique singletrack around and over the massive rocks, the trail provides access to some of the best bouldering spots in central NJ.
  4. Montezuma
  5. Chunky Monkey