Know the New Hiking How-tos
Torne Mountain/Osio Rock Loop from Otter Hole
Directions to trailhead
Take I-287 to Exit 53 (Bloomingdale) and turn left onto Hamburg Turnpike. Upon entering Bloomingdale, the name of the road changes to Main Street. In 1.3 miles (from I-287), you will reach a fork in the road. Bear right, and in another 0.1 mile, bear right (uphill) onto Glenwild Avenue. Continue ahead for 3.2 miles to a parking area on the right side of the road
This rugged, figure-eight double-loop trail climbs two peaks at the southern end of Norvin Green State Forest – Torne Mountain and Osio Rock. Although it is less than three miles long, the hike may seem somewhat longer, as it involves considerable ups and downs on rocky trails.
At the eastern end of the parking area, at the sign “Welcome to Bloomingdale,” cross Glenwild Avenue. On the south side of the road, you will notice a blue-blazed post, marked “HB.” Follow the blue-blazed Hewitt-Butler Trail, which climbs the hill and then turns right, heading west and parallel to the road on a rugged footpath, for about a quarter mile. Here, with the road visible to the right, you’ll cross the red-blazed Torne Trail.
Continue ahead on the blue-blazed Hewitt-Butler Trail, which begins a steady climb of Torne Mountain. In about 15 minutes, you’ll come out on a open rock ledge, with limited views to the west and north. When there are no leaves on the trees, Buck Mountain is visible to the north.
Proceed ahead, following the blue blazes along the ridge of Torne Mountain. After crossing several open areas with limited west-facing views, you’ll arrive at a large open area with two cedar trees, two balanced glacial erratics, and a stone bench. This beautiful spot affords unobstructed views to the west and south.
The trail now begins to descend. Soon, you’ll reach a junction with a black-dot-on-blue side trail. Here, you should turn left to stay on the blue-blazed trail. Just ahead, you’ll come to a southeast-facing viewpoint over Osio Rock (the next peak you will climb), with the New York City skyline visible in the distance. After descending some more, you’ll come to another view of Osio Rock. The trail now descends on switchbacks, with Osio Rock visible to the left along the way. After a steep descent on log steps, the trail levels off.
Just beyond, you’ll pass the other end of the black-dot-on-blue side trail and descend into a ravine with an intermittent stream. The red-blazed Torne Trail crosses here, but you should turn right to stay on the blue-blazed Hewitt-Butler Trail. Follow the blue-blazed trail, which climbs through dense thickets of mountain laurel, levels off, then resumes its climb.
After passing a jumbled formation of huge boulders on the right, the trail again briefly levels off, then resumes a steady climb to reach a limited east-facing viewpoint. A short distance beyond, it emerges onto a rock ledge -- the summit of Osio Rock. This peak affords a spectacular 360-degree view. The large body of water visible on the left is the Wanaque Reservoir, and the curved elevated roadway on the right is I-287. This is a good place to take a break.
When you’re ready to continue, follow the blue blazes as the trail descends from Osio Rock. On the way down, you’ll pass a southeast-facing viewpoint over the private Lake Kampfe. The trail now descends more steeply on a rocky footpath, with a rocky peak studded with pines visible ahead. After a short level stretch, the blue-blazed Hewitt-Butler Trail ends, just before a stream, at a junction with the red-blazed Torne Trail.
Turn right onto the Torne Trail, which heads north on a level footpath parallel to the stream, then begins to climb through a ravine. After passing an interesting cascade on the right, you’ll once again cross the blue-blazed Hewitt-Butler Trail. Continue to follow the red-blazed Torne Trail, which climbs steeply through large boulders, then continues to ascend on a very gentle grade through an attractive valley.
The Torne Trail descends from the crest of the rise, again crosses the blue-blazed Hewitt-Butler Trail, and ends just before reaching Glenwild Road. Turn right onto Glenwild Road and follow it for a short distance to the parking area where the hike began.