Yellowstone National Park

Larger than the states of Delaware and Rhode Island combined, the world’s first national park is a literal hotbed of activity.

Covering over 2 million acres, the vast wilderness of the park sits atop an active supervolcano, making it one of the best places on earth to observe multitudes of geothermal phenomena. There’s even a natural “fountain” that is famous for rewarding visitors for being on time—though there’s no reward for throwing a lucky penny. 

Though it has been 70,000 years since its last lava flow and 2.1 million years since its last eruption, Yellowstone’s volcano makes its presence known in a variety of natural aboveground wonders. The Mammoth Hot Springs emit steam daily across a limestone mountainside, and the Morning Glory geothermal pond shows its vibrant colors due to the types of bacteria that survive in its extremely hot temperatures. 

Yellowstone’s most famous feature? Geysers. A form of hot spring that, after building up a certain amount of pressure, erupts hot water and steam. The park is home to the largest geyser field on earth including the Steamboat Geyser, long claimed to be the world’s tallest plume. However, the most famous site in Yellowstone’s parkland is a “loyal” geyser. Gaining the nickname “Old Faithful” due to the predictability of its eruptions, the regular geyser spews a fountain of steam approximately every 92 minutes.

In recent decades, scientists have begun questioning Old Faithful’s reliability, as, like a spurned lover, the spout’s eruptions have not been as regular as earlier in the park’s history. While possibly due to natural causes, human interaction hasn’t exactly helped, with thousands of coins, debris, and even dirty laundry thrown into the geyser’s springs for a quick wash. To combat the negative impact on humanity, park officials have levied major fines on any visitor who launches an object towards the steadfast spout. Hopefully, the geyser is as forgiving as it is faithful, and will soon resume the regularly scheduled program.