Underrated experience. The path is a very wide rocky path. Primarily used by snowmobiles in the winter although apparently ATV's illegally use it as well. I went on a Sunday afternoon and didn't see a soul all the way up and back. Fairly easy hike, not very strenuous and rewards you with amazing views of the Catskills and the Schoharie Reservoir. Breathtaking. Lots of different birds and flowers on the trail. The trail was very clean, no litter.
Warning: This doesn't look like a trail. Or anything. Easiest way to approach is from Heisinger Rd. It is your first gate on the left, I just parked in front of it. There is no marker of any sort to indicate this path goes to Bearpen and easy to miss, there are still old "no trespassing" signs from before the DEC bought it as well that could easily deter someone if they didn't know they were old The trail is not marked but you'd have to be missing some brain cells to get off the path as it is huge and clear.
All in all it is seriously a shame that this trail is not used much. It has seriously phenomenal views and this mountain has a ton of history. There are some cool old historical relics at the top from when this mountain was used for skiing.
Definitely worth the trip. Took me two hours up and back, took probably one or two breaks going up for about five minutes to catch my breath.
Bearpen Mountain is one of the required mountains for the Catskills 3500 Foot Club. It is an easy limb and can be hiked from bottom to top using a road (more suitable for snowmobiles and four-wheelers than actual vehicles). There is a hunter's shack (Tar Paper) at about the one mile mark, the trail also splits at this point, going off to the right leads to another mountain but this is not a marked trail. Following the main road/trail leads to the top of Bearpen. You can cut off at least half a mile from the road by taking an unmarked foot trail. This foot trail is actually shown on the NY/NJ Trail Conference map and is not only a shorter route but also a significantly easier one. We only had one good view, it was a partial view and it was at the peak. I would not recommend doing this hike in the summer. The views would be much better when the leaves are off the trees. Also, we encountered four-wheelers at three different points on the trail. A total of 9 different vehicles. In the winter, this trail is used by snowmobiles so you should also take that into consideration.