This is my favorite classic. It was filmed a little west of Philadelphia, PA when I was 13, in 1957, and released the next year. Then in 1970, I found myself working the very same county as a rookie PA state trooper. I have always enjoyed checking out the different places where scenes were filmed. I knew the owner of the Downingtown Diner well, and he had a road sign out front which told all passing motorists that this was the "home of the blob". The theater scene was in Phoenixville, near Valley Forge Park and it is still showing films today!