My troop's been to Sabattis Scout Reservation twice over the past four years. Sabattis is between Long Lake and Tupper Lake in the Adirondacks.
It's the best camp we've ever been to - it's on Lows Lake, a 2800 acre lake (no motorboats allowed) where all of the shoreline (except for the camp) is owned by the state. And there are many other lakes and rivers that are easily accessabile - all on state land. There are miles of shoreline to explore, bogs to paddle through, rocks to jump from, and beaches to hang-out at. And sprinkled throughout this state land are first-come-first-served free