Herkimer Reservoir.

Herkimer Reservoir is a one-acre impoundment in the Old Forge area — small enough that "reservoir" overstates the case, but it holds its place on the map as a named water in the western working forest. No public access data on file, no fish stocking records, no trail references in the DEC inventory — likely private, likely built for an old logging operation or a camp water supply that predates the recreational infrastructure around town. If you're looking for fishable stillwater near Old Forge, you want the Fulton Chain, Fourth Lake, or any of the ponds off the Moose River Plains — Herkimer is a dot on the survey map, not a destination.