It’s Halloween season – the perfect time to take a road trip to a spooky national park for some frightful fun and witness a supernatural phenomenon. The experience is only enhanced by the fog drifting out of valleys, leafless trees in the forests and chill air that are typical of the fall. Luckily for the adventurer in you, you can combine a camping trip in the wilderness with an unnerving thrill that you will remember forever. The U.S. is home to several national parks where multiple guests, at different times, have reported eerie events.