Not a camper or ranger, but an archeologist.
A few years back we were doing a massive survey in the middle of nowhere in the interior of British Columbia. All the crew had gone home and it was just my boss and myself left for a few days to follow up and confirm some coordinates and finish some mapping.
We head out from the motel an hour or so into the bush, in the middle of nowhere along deactivated logging roads. The closest town is miles and miles away. We hike out to this one area we had found a few weeks previously. For some reason the whole area just felt off.
So, we get down to business and about 15 minutes after being hunched over mapping, there is this weird deafening “WOMP” sound. Like, I could feel pressure in my ears. I immediately looked at my boss about 20 feet away and he is white as a ghost staring back at me. While standing there, it happens again “WOMP!” ear pressure and chest pressure like I was just squeezed. Chills erupt all over my body and every hair is standing on end. My boss just looks at me and says, “let’s go!” We grab all of our stuff and speed hike back to the truck.
We never discussed it.
No clue what it was but I have never been so freaked out in my life. 10 years later, I still get the chills.