Lounsbury Pond is in Blue Mountain Reservation and not really that close to the Appalachian Trail or Beaver Pond. Sterling Forest is about 45 minutes away. You cannot camp at Blue Mountain Reservation. Stillwater Lake is in Putnam County and the trail near it is unmarked and not named. Says Jane Daniels
There's a splendid grade IV(V+) bit of whitewater close by on Penlolopen Brook, the 1-mile-long Queensboro Lake to a mile above 9W sector. This part
of Penlolopen Brook is magnificent for those with a lot of whitewater familiarity. A nearby grade IV-V whitewater stretch can be encountered on Popolopen Creek; the to Popolopen Bridge segment is 4 miles long.