Yellowstone National Park is often recognized for its intense geothermal activity, including the world’s most concentrated collection of geysers and hot springs. Beneath these thermal features, however, lies a landscape defined by dramatic, rugged mountain ranges that form the park’s imposing perimeter. This mountainous setting, a product of powerful geological forces, creates the high-elevation environment responsible for the vast plateaus and deep canyons within the park. The geography of Yellowstone, extending across parts of Wyoming, Montana, and Idaho, is a result of both ancient mountain-building events and more recent volcanic processes.
The Defining Mountain Ranges of Yellowstone
The majority of Yellowstone’s mountainous terrain is concentrated along its eastern and northwestern boundaries, distinguishing the park’s perimeter from its central volcanic plateau.
The Absaroka Range
The largest and most imposing of these is the Absaroka Range, which forms a continuous wall along the entire eastern edge of the park and wraps into the northeast corner. This extensive range features the park’s highest summit, Eagle Peak, which reaches an elevation of 11,358 feet. The Absarokas are primarily composed of volcanic rock layers, specifically ash and pumice, resulting from eruptions that occurred approximately 50 million years ago.
The Gallatin Range
In contrast, the Gallatin Range dominates the park’s northwestern section, extending into Montana. This range is characterized by a core of Archean-aged gneiss, a rock that dates back billions of years, overlain by younger sedimentary layers. The highest point in the Gallatin Range is Electric Peak, which stands at 10,965 feet, marking the northern boundary of the park. The southern extent of the Gallatins was truncated during one of the supervolcano’s ancient eruptions, illustrating the interplay between mountain uplift and volcanic destruction.
Internal Ranges
Two smaller, entirely internal ranges also contribute to the park’s topography. The Washburn Range, located in the north-central area, is home to Mount Washburn, a popular hiking destination reaching 10,219 feet. To the south, the Red Mountains are a compact group near Heart Lake, with Mount Sheridan rising to 10,308 feet. The Beartooth Plateau, a high-elevation offshoot of the Absarokas, influences the park’s extreme northeastern boundary.
The Grand Teton Range and the Southern Boundary
The Grand Teton Range, a visually striking feature south of Yellowstone, is often mistakenly considered a part of the park itself. While geographically close, they are separate entities, with the Tetons defining Grand Teton National Park. The northern boundary of Grand Teton National Park lies just 10 miles south of Yellowstone’s southern border, connected by the John D. Rockefeller Jr. Memorial Parkway. The Teton Range is geologically distinct, representing one of the youngest uplifted fault-block mountains in the Rocky Mountains. These peaks rose sharply along a fault line, resulting in their nearly vertical appearance without significant foothills, which contrasts with the volcanically shaped mountains of Yellowstone. The proximity means they share the vast Greater Yellowstone Ecosystem, connecting them ecologically despite their separate identities.
Elevation and the Path of the Continental Divide
The high elevation of Yellowstone’s mountain ranges creates the Continental Divide of the Americas. This line weaves through the mountainous southern and central portions of the park, acting as a drainage boundary for precipitation. Water that falls on the eastern side flows toward the Atlantic Ocean or the Gulf of Mexico via major rivers like the Yellowstone and Missouri. Conversely, precipitation on the western side is directed toward the Pacific Ocean, primarily feeding the Snake River system. The Divide crosses high ground like the Two Ocean Plateau and the Madison Plateau. This mountainous crest captures immense amounts of winter snow, which melts and sustains the headwaters of several significant rivers. The park’s overall high elevation dictates the harsh weather patterns and unique alpine ecosystems that exist above the treeline.