Last summer my wife and I went to Independance Hall in Pa. There is a security tent with rent a cops and a NPS ranger who is armed. There is full blown security, metal detector etc., like the airports.As I entered the tent, before going through the metal detector, I advised security I had one of the small keychain Swiss Army knives and would it be a problem, or should I leave. The rent a cop took it and handed it to the ranger. I went through security and then got a lecture from the ranger. According to the ranger, I shouldn't have even entered the tent with it. Fortunately, I didn't even take the knife I normally carry. After the lecture, the ranger returned the knife, advising me to not use it on the property.