Half a mile west of the south limb of the Cushetunk horseshoe, in abandoned limestone quarries, are the remains of the kilns where the rock was burned. The rock has a peculiar blue color, possibly due to its manganese content. The Brunswick shales of the interior valley are open, while the contact with the trap rock and border conglomerates is generally indicated by the forest which covers the ridge. In 1958 a natural horse-shoe shaped valley in the rolling hills of Hunterdon County was damned, and today 55 billion gallons of water fill this area, known as Round Valley Reservoir. It is the deepest in the state.
Many fisherman come here.
Lots of boats. Hike along a portion of the nine-mile trail.