I remember taking a coach tour of our western National Parks a few years ago, and I was astonished to see signs all over the place probibiting bringing firearms in Yellowstone National Park. Right next to those signs were other signs warning of the presence of grizzlies in the area. Didn't compute then, doesn't compute now.
Obviously unconstitutional prohibitions.
Some main highways run through Yellowstone. I'd bet that hundreds [if not thousands] of travelers a day rightly ignore those 'laws'.