Jackson Hole is a small town which owes its existence to the nearbye Grand Teton National Park.. The Tetons are the model for the perfect mountains - they rise from a flat plain to over 4ooom at an almost constant angle of slope ie steep. At their feet is a chain of glacial lakes fed by melt water from high living glaciers (each with its own cirque). Between the peaks are hanging valleys one with its own special character. The peaks, though young consist of hard old granite from deep inside the earth’s crust. Bears roam wild, eagles fly overhead.
To the north, on the banks of the Firehole River, lies Yellowstone National Park which, has more than its fair share of the world’s geysers, in fact as many as the rest of the world put together. The geysers are just one manifestation of the extensive plumbing going down 1000 feet and more into the earth’s crust which here is very thin - there are springs, pools, fumeroles and mud pots. The most extensive collection of geysers is in Upper Basin where Old Faithful is to be found. Not all erupt with its regularity (every 90 mins.) but some are even more spectacular if you can sit and wait 20 or 30 years until their next eruption comes along. Grand, Riverside, the Beehive are three of the best, not least because they erupt most days so the wait is bearable. For colour Grand Prismatic Spring takes the prize.
Between Old Faithful and the Canadian Rockies is the Road to the Sun passing through Glacier National Park. consisting largely of sedimentary rock deposited some 3-5 miles thick around 1.6 billion years ago. The park was formed around 70 million years ago when these strata began to rise and then break off and slide 35 miles east and then sculpted by the glaciers of the great ice age.
Lake Louise and Banff National Parks in Canada are at the eastern edge of the Rockies. The glaciers, waterfalls and waterfalls provide a spectacular landscape for 2-300 miles.