Carrying in a national park.

I am going to Mammoth cave today and while I can carry in the park as no state law or federal law forbids it, I cannot carry in the cave. I guess the cave is designated as a federal building? Now while I don't depend on my gun as crutch to feel comfortable in public, I do have a very real fear that I might wake up some ancient mummies that are buried in the cave and I am only left with a buck knife to carry. The tour I am going on is an unguided tour so it will just be me the wife and kids. Also it will be pretty dark so easy enough to conceal. Would you chance yourself to 5 years in federal prison to defend your family when there is little chance you would be detected? via /r/CCW http://ift.tt/2e9HLEJ