In 1932, many visitors saw Glacier National Park by horseback. One multi-day trip took clients along the north face of Boulder Peak, where they encountered Boulder Glacier. At the time (as seen in the first photo), a cavernous entrance into Boulder Glacier dwarfed the 4 onlookers
Fast-forward to 1988, when Ranger Jerry Desanto hiked over Boulder Pass. Using the mountains in the background—Chapman, Cleveland, and Peak 9125—Desanto found where the original 1932 photo was taken and took one of his own.
This was one of the first efforts to repeat a glacier photo from early in the park's history.

In the 56 years between these two pictures, the ice cave collapsed, and the glacier receded out of the frame. Today, Boulder Glacier is too small to be considered active.
Repeat glacial photography has been used to show glacial change around the world since the late 1800's. Since Desanto's 1988 photo, the USGS has repeated over 80 photos of 20 different glaciers in Glacier National Park.
The differences between photos, sometimes taken over 100 years apart, offer dramatic and powerful glimpses into the lives of these alpine glaciers.
Moving forward, what glaciers do you want to see repeat photos of? What will fill the frame of these photos in the next 100 years? #GlacierMovingForward
Photo Credits:
George Grant, GNP Archives, 1932
Jerry DeSanto, K. Ross Toole Archives, 1988

These photos of Boulder Glacier and the Boulder Glacier basin were taken on the traditional land of the Amskapi Piikuni, Kootenai, Selis, and Qlispe People in 1932 and 1988 📍
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