West Yellowstone, MT
The only airport with the name "Yellowstone." 6,649ft elevation — density altitude is a real consideration. Seasonal commercial service June-October; closed November-April when the snow takes over. West Yellowstone, the town, is the western gateway to the park — Old Faithful is 30 miles by car, Grand Prismatic Spring 28 miles. The 1909 Oregon Short Line Railroad terminal still stands in town. National Park Service overflight advisories apply within the park boundary. One of the most scenic approaches in the lower 48 — the Madison River valley funnels in from the west, surrounded by the Gallatin and Madison ranges.
The first national park in the world (1872), 3,468 square miles straddling the Wyoming-Montana-Idaho border. Yellowstone sits over the Yellowstone hotspot — a magma plume that has produced three caldera-forming "supervolcano" eruptions in the last 2.1 million years, the most recent 640,000 years ago. The current caldera is 30 by 45 miles. Geothermal features result: 10,000+ hot springs, 500+ geysers (more than the rest of the world combined), Old Faithful erupting on a 90-minute cycle, the bright bacterial mats around Grand Prismatic Spring. The Yellowstone River carved the Grand Canyon of the Yellowstone with its 308-foot Lower Falls. Bison herd is the largest in the country (~5,000), grizzlies have returned to ~1,000, the wolves reintroduced in 1995 are at ~100. Most-visited national park in the US most years. From the air, the Upper Geyser Basin reads as a white mineral-stained clearing in the forest, with steam plumes visible 50-plus miles out on cool mornings; Grand Prismatic Spring shows its rainbow banding best from directly overhead.
The Yellowstone caldera is one of the largest active volcanic systems on Earth. The Upper Geyser Basin, containing Old Faithful and 150+ other geysers, appears from altitude as a white mineral-stained clearing in the forest with steam plumes visible from 50+ miles on cool mornings. The Grand Prismatic Spring (the largest hot spring in the US) shows its rainbow colors best from directly above. Yellowstone National Park has standard NPS overflight advisories.
The Teton Range rises 7,000 feet directly out of Jackson Hole valley with no foothills — one of the steepest mountain fronts in North America. Grand Teton, the highest peak at 13,775 feet, was first summited in 1898; the range was named by French-Canadian trappers who called the three central peaks "les trois tétons" ("the three breasts"), a name that has not aged well but stuck. The Snake River runs along the eastern base of the range; from Jackson Hole Airport (KJAC, the only commercial airport inside a US national park) the entire range fills the western horizon. Glaciers — Teton, Schoolroom, Middle Teton, Falling Ice — still cling to the upper cirques despite a century of retreat.
A Smithsonian-affiliated natural history museum on Montana State University's campus, world-renowned for its dinosaur paleontology collection. Paleontologist Jack Horner — the model for Alan Grant in Jurassic Park — built the collection from Hell Creek Formation digs across eastern Montana, and the result is one of the world's most important T. rex and Triceratops holdings. The Siebel Dinosaur Complex houses fossils still embedded in matrix, alongside fully mounted skeletons. Beyond dinosaurs: a planetarium, a working homestead exhibit, and rotating regional history shows. Plan on 3+ hours; a serious museum, not a stop-by.