
Yellowstone is the first and oldest national park in the world and covers 3,472 square miles (8,987 km²), mostly in the northwest corner of Wyoming. The park is famous for its various geysers, hot springs, and other geothermal features and is home to grizzly bears and wolves, and free-ranging herds of bison and elk.
Long before any recorded human history in Yellowstone, a massive volcanic eruption spewed an immense volume of ash that covered all of the western U.S., much of the Midwest, northern Mexico and some areas of the eastern Pacific Coast. The eruption dwarfed that of Mt. St. Helens in 1980 and left a huge caldera. Yellowstone typically erupts every 600,000 to 900,000 years with the last event occurring 640,000 years ago. Its eruptions are among the largest known to have ever occurred on Earth, producing drastic climate change in the aftermath. The park was named for the yellow rocks seen in the Grand Canyon of the Yellowstone - a deep gash in the Yellowstone Plateau that was formed by floods during previous ice ages and by river erosion from the Yellowstone River.
In 1872, Yellowstone became the first National Park reserve declared anywhere in the world, by President Ulysses S. Grant. In 1978 it was designated a World Heritage Site by UNESCO.
Geological characteristics form the foundation of an ecosystem. In Yellowstone, the interplay between volcanic, hydrothermal, and glacial processes and the distribution of flora and fauna are intricate and unique. The topography of the land from southern Idaho northeast to Yellowstone results from millions of years of hotspot influence. Some scientists believe the Yellowstone Plateau itself is a result of uplift due to hotspot volcanism.
The park is the core of the Greater Yellowstone Ecosystem, one of the largest intact temperate zone ecosystems remaining on the planet. Black bears, grizzly bears, deer, elk, bison, bighorn sheep and wolves can all be found within the park borders.
Geothermal features include geysers, mud pots, hot springs, fumaroles, and others. This is all because of the active volcano that Yellowstone sits on top of. Geothermal features are formed from superheated water heated by the volcano. The pressure is so intense that it gets released into the air as hundreds of gallons of steaming water, or, when the pressure is not as intense, hot springs or mud pots are formed. Various colors of the pool are due to different types of bacteria growing in different temperatures. A good way to learn about the geothermal features is through the Young Scientist Program. Please check with a Ranger at the Old Faithful Visitor Center.
The weather in Yellowstone National Park can change very rapidly from sunny and warm to cold and rainy, so it's important to bring along extra layers of clothing which can be used as needed.
Many visitors believe they can visit all 2.2 million acres of Yellowstone in 1-2 days - all the while staying within sight of their car or tour bus. To truly appreciate this vast park, get off the park roads and paved tourist paths.
Yellowstone is world-famous for its natural heritage and beauty - and for the fact that it holds half the world's geothermal features, with more than 10,000 examples. Travelers to Yellowstone can view more than 300 geysers (such as "Old Faithful"), pools of boiling mud, and an amazing assemblage of wildlife, such as grizzly bears, wolves, bison and elk, all while standing on the surface of the Earth's largest known "super-volcano".
The principal airport serving Yellowstone is the Jackson Hole Airport (IATA: JAC) [2] located within Grand Teton National Park. Other airports can be found in Idaho Falls (IATA: IDA) [3] in Idaho; Billings (IATA: BIL) [4], Butte (IATA: BTM) [5], and Bozeman (IATA: BZN) [6], all in Montana; and Cody (IATA: COD) [7] in Wyoming. Be aware that the alternative airports may have less airline service than does Jackson Hole.
The park has 5 entrances. The nearest cities to each entrance are given. Most are within 5 miles of the park boundary.
Most visitors use private vehicles to get around inside Yellowstone National Park. There is no public transportation available within the park. Roads can become very crowded whenever people stop to view wildlife; use pullouts, and be respectful of other motorists to help avoid bear-jams.
Xanterra Resorts provides bus tours within the park during the summer season. The Lower Loop Tour departs from locations in the southern part of the Park only. The Upper Loop Tour departs from Lake Hotel, Fishing Bridge RV Park, and Canyon Lodge to tour the northern section of the park only. The Grand Loop Tour departs from Gardiner and Mammoth Hot Springs Hotel to tour the entire park in one day. During the winter season snowcoach tours are provided from various locations. Call (307) 344-7311 for information or reservations.
In addition, during the summer season, commercial businesses offer tours originating from many area towns and cities. During the winter season, some businesses provide snowcoach tours for most park roads or bus transportation on the Mammoth Hot Springs to Cooke City road.
Cycling in the park can be a very rewarding experience, but due to the great distances in the park some additional planning to ensure that lodging is available each night. The park reserves a number of campsites for cyclists, but during the busy summer season it is probably best to reserve sites in advance wherever possible.
Every major village within the park offers food, camping supplies, and souvenirs for sale, although these stores all close during the winter months.
Gasoline and automotive services are available in the following locations:
Most of the villages sell food supplies and may offer snack bars. The following restaurants and cafeterias are also available: