My home town still has the Colonial powder house sitting atop (strangely enough) Powder House Hill.
I tried to google it to find a picture, but no luck. I assume you are from South Berwick. I don't know of any powderhouses still standing near me. I live just west of Harrisburg, PA and this area of PA was settled in the mid 1700's. (At least that was when towns started to become incorporated.