This image is a look into the depths of the Morning Glory Pool. It is one of the easiest thermal vent pools for tourists to see, but this has led to the deterioration of it’s colors.

The caption states:

3954 – Morning Glory Pool, Yellowstone National Park. This is perhaps the most noted of the dozens of beautiful hot water pools occurring in the park.

–The deep blue of the pool shown in this image is long gone. Tourists have dropped so much foreign material into the pool that it’s biome has changed, and the blue is completely gone, replaced with a pale green ringed by orange and red.

This image likely dates from the 1940s.

This image shows the driver’s entrance and main door to the Old Faithful Inn. In the background is a artist’s rendition of the eruption of Old Faithful geyser, world famous for its clock-like precision of timed eruptions.

The caption states:

OLD FAITHFUL INN AND GEYSER

Old Faithful Inn and Geyser are in the upper Geyser Basin of Yellowstone where the largest and finest geysers in the world are gathered within a space of a mile. About Old Faithful is another of the Park community centers and supply points with stores, camps, museum, bath house, etc.

— The exterior look of the Inn has changed little over the years. The geyser is predictable to a range of about 15 minutes, averaging an eruption every 74 minutes.

This image dates from the 1940s.

This image shows the spectacular view of Tower Falls, an easily accessible feature located in Yellowstone National Park in Wyoming.

The caption states simply:

Tower Falls near Tower Junction in Yellowstone Park.

The falls are 132 feet in height. Most notable is the boulder shown at the edge of the precipice. It is no longer there, having succumbed to erosion and gravity in 1986.

This image likely dates from the 1940s.

This postcard shows the once-common sight of a bear approaching a passing visitor to Yellowstone Park, and the visitor stopping the car to experience a close encounter with the wild animal. Decades ago, this was not understood to be very dangerous, and over time increasing numbers of visitors were attacked or mauled by bears in such situations.

The caption states:

BEARS ON HIGHWAY

YELLOWSTONE NATIONAL PARK

Long renowned as a refuge for wildlife, Yellowstone contains a wide variety of animals. Most popular and best known are the yellow and brown bears which are frequently seen along the highways through the park.

— In recent decades bears have been relocated to more remote areas when possible to reduce the likelihood of violent encounters with visitors and campers. People are given instructions and training on how to avoid attracting bears to their camps and especially to their food.

The automobile in this picture places the card in the late 1940s.

This postcard shows the suggestively named Mae West Curve, part of the mountain-crossing Highway 12 in Wyoming, as it was then known. The highway as since been renamed US 212, and passes through the mountains west and north of Yellowstone National Park before entering the park from the Montana side.

The caption states:

#4050 – Mae West Curve on the Beartooth Highway (U.S. 12) to Yellowstone Park via Red Lodge and Cook City.

— Mae West was a popular and deliberately provocative actress of the early days of talking movies. Her large breasts were the most noted feature, and Mae West also gave the name to a style of personal flotation device (life jacket).

This card is likey from the 1940s.