The red tour buses shown are original and still in use today. They are Model 706 built by the White Motor Company from 1936-1939. Called Jammer buses, they do tours of the Going To The Sun across Glacier National Park. They were rebuilt in the early 2000s to run on propane and install automatic transmissions.
The movie was filmed in 3-D, hence the scenes of an avalanche, a forest fire, steep glacier cliffs, and the sparking electrical live wire.
The hotel featured in the movie is the Glacier Park Hotel in East Glacier Park, MT, now called the Glacier Park Lodge.
One of a string of "resort thrillers" made in the 1950s, including Ein Satansweib (1951) and Mörder ohne Maske (1953), both set in Mexico, Niagara (1953), set in Niagara Falls, NY, and Der unsichtbare Dritte (1959) at Mt. Rushmore.
You have to love Hollywood. Louise Graham (Piper Laurie) treks across mountains in a dress, hose, high heels, and immaculate hair.