this cache is in an extra small container in a park in Alton Bay. There is a swimming beach next to it with a small parking lot across the street which is where you can park. Be careful crossing the street - there is a blind spot here and cars tend to go fast past this area and can come close to the cache itself, so be aware of your surroundings as you're looking. After finding the cache there are a couple of nice spots to sit and relax and enjoy the view.
My mother-in-law is in the garden club that is responsible for maintaining the nice potted flowers and plants that you see. This cache would likely be accessible in winter.
My family and I have a powerboat on the lake in Alton Bay and we used to keep it at the dock that is at the bottom of the set of stairs that you can see when you are near the cache. We've since moved our boat to another dock a bit further down the road.