I Lava Yellowstone!
Yellowstone National Park, which is situated in Wyoming and gets its name from the volcano that lives there, is one of the most well-known national parks in the country. And no, visiting Yellowstone is still acceptable—in fact, it’s highly recommended—but this volcano is still active.
Fear not—the last significant eruption occurred 640,000 years ago. But specialists keep an eye out for activity there all the time. If it broke out, its effects would be felt in every state in the union.