Lately there has been discussion of abandonment of the Tahawus Rail Line along the Boreas River that was constructed illegally during World War II, removing the rail and turning it into a multi-use trail for biking and hiking in summer and snowmobiles in winter. While you can walk it now, it's technically still an active rail line, and you have to step over ties and rails and probably is trespassing.
The trail would be a nice one, as over the 5 miles between Northwood Club Road and Moose Club Way is only about a 150 foot elevation gain, so it's a very gentle hike into remote wilderness, on a route that could be a nice leisurely hike or bicycle ride into very remote country.
The Roosevelt Truck Trail runs 2 1/2 miles from NY 28N to County Route 28 - Boreas Road. The gated truck trail is a fairly flat walk or bicycle ride through remote wilderness, only accessed by administrative vehicles and persons with disabilities.
2.5 miles North of Hoffman's Road, following the Hoffmans Notch Trail aka Big Pond Trail there is a designated campsite located a spur of the trail going down to the lake.
Access to Horseshoe and Bullet Pond is via Horseshoe Pond Road which runs parallel to and intersects Hoffman Notch Road in Schroon. Bullet Pond is only accessible by a bushwhack through wilderness, it's the more developed pond, while Horseshoe Pond is much closer to the road and much more wild.