A view of Middle Sister, one of the Three Sisters volcanic peaks located in the Cascade Range in central Oregon.

North Sister viewed from McKenzie Pass. North Sister is one of the Three Sisters volcanic peaks located in the Cascade Range in central Oregon.

Five photos show scenes from around Camp Loon Lake, including a view of the Three Sisters mountains.

Four photos of the area around Camp Rigdon, including views of the Three Sisters and Mt. Washington. Handwriting on the page reads, "Donated by the Supt. of the Willamette N.F."

Ten photos show scenes in and around Camp Belknap, including general views of the camp, the officer's quarters and doctor's cubicle, the McKenzie River, and the Three Sisters.

Nine photos show scenes in and around Camp Belknap, including camp members, general views of the camp, the Three Sisters, McKenzie Pass, and Hand Lake. One man is identified as Alden Parker.

Negative of a photographic postcard showing snowy mountains in the Oregon Cascade Range. Pictured (left to right) are the Three Sisters, Mount Washington, and Three Fingered Jack. Handwriting on negative reads, "Three Sisters, Mt. Washington, Three Finger Jack - Oregon. Christian S-353."

Negative of a photographic postcard showing a cracked patch of ice and snow along the summit ridge of a mountain. The mountain peak is in the background. Handwriting on negative reads, "Snow Fields - Three Sisters - Oregon. Christian S-371."

Negative of a photographic postcard showing South Sister mountain in the Oregon Cascade Range. The peak of the mountain is obscured by clouds. Taken from a meadow near the peak. Handwriting on negative reads, "South Sister of the Three Sisters - Ore. Christian S-383."

Negative of a photographic postcard showing a view of Scott Lake and the Three Sisters mountains in the background. Handwriting on negative reads, "Scott Lake McKenzie Highway, Oregon. Christian S-264."

Negative of a photographic postcard showing Elk Lake with a view of South Sister in the background. Taken from the shore of the lake. Broken Top mountain is visible to the right. Handwriting on negative reads, "Elk Lake near Bend, Oregon. Christian S-254."

Negative of a photographic postcard showing a person sitting on a rock, looking at a view of North and Middle Sisters in the distance. Both mountains have snow on them. The person's back is to the camera. There are large rocks in the foreground. Handwriting on negative reads, "North and Middle Sisters - Oregon. Christian S-135." Handwriting also notes elevation of North Sister as, "el. 10094" and elevation of Middle Sister as, "el. 10053."

Negative of a photographic postcard showing a lake and the Three Sisters mountains in the Cascade Range. The mountains are reflected in the water of the lake. The landscape is snowy. Handwriting on negative reads, "Winter Reflections - Three Sisters, Ore. Christian S-357."

Negative of a photographic postcard showing a glacier on a mountain. A mountain peak is visible in the background. Handwriting on negative reads, "Glacier between Middle and North Sisters, Ore. Christian S-389."

Negative of a photographic postcard showing a view of the Cascade Range mountains from Lava Butte Road in Oregon. View includes Mount Bachelor, Broken Top, and the Three Sisters mountains. Handwriting on negative reads, "Lava Butte Road - Oregon. Christian S-285."

Negative of a photographic postcard showing a road with a view of the Three Sisters mountains in the Cascade Range in Oregon.

Negative of a photographic postcard showing a view of Middle Sister and North Sister mountains from McKenzie Pass in the Cascade Range in Oregon. The view is from behind a rock wall, tinted blue, in the foreground. The mountains are covered in snow. Handwriting on negative reads, "McKenzie Pass, Oregon. Christian S-242."

Negative of a photographic postcard showing a highway in the high desert of Central Oregon. There is a view of the Three Sisters mountains in the Cascade Range in the distance. Handwriting on negative reads, "Redmond - Sisters Highway - Oregon. Christian S-243."

Negative of a photographic postcard showing a person standing on a large lava bed in the McKenzie Pass area of the Cascade Range in Oregon. The lava bed is surrounded by a forest. Middle Sister and North Sister mountains are in the background. Handwriting on negative reads, "Lava Beds - McKenzie Pass, Oregon." The sky in the photograph has been colored blue.

Negative of a photographic postcard showing a person looking through a telescope at the D. Wright Observatory on the McKenzie Pass in the Cascade Range in Oregon. Lava beds and trees stretch into the distance and Middle Sister and North Sister mountains are in the background. There is a directional marker in the foreground. Handwriting on negative reads, "D. Wright Observatory - McKenzie Pass, Ore. View from Observatory. Christian S-160A."

Negative of a photographic postcard showing a river in the foreground and a view of South Sister mountain in the background. Handwriting on negative reads, "South Sister from Fall Creek, Oregon. Christian S-184."

Negative of a photographic postcard showing a road on the McKenzie Pass in the Cascade Range in Oregon. Middle Sister and North Sister mountains are in the background. Handwriting on negative reads, "Along McKenzie Pass, Oreg. Christian S-161."

Photograph of crops growing in a vast agricultural field near Sisters, Oregon. The Three Sisters mountains of the Cascade Range are visible in the background. Handwritten note on the back of the print reads, "Farming Country and the Three Sisters (from a point 7 mi. E of the town of Sisters.)" Stamps on the front and back of the print indicate a 1911 copyright by Kiser Photo Co. for SP&S Railway.

Photograph of the Three Sisters mountains in the Cascade Range, taken from a road between Redmond and Sisters, Oregon. High desert landscape in the foreground. Handwriting on the back reads, "The Three Sisters, as seen from the Redmond, The Sisters Road." Stamps on the front and the back indicate a 1911 copyright by Kiser Photo Co. for SP&S Railway.

Irene Finley, Pete the dog, and an unidentified woman standing near the porch of the M. Bailey house. The Three Sisters mountains are visible in the distance.

A view of the M. Bailey house with the Three Sisters mountains visible in the distance.

Irene Finley, Pete the dog, and two unidentified people standing near the porch of the M. Bailey house. William Finley Jr. stands to the side on the porch rail. The Three Sisters mountains are visible in the distance.

Irene Finley, Pete the dog, and an unidentified woman standing near the porch of the M. Bailey house. William Finley Jr. stands to the side on the porch rail. The Three Sisters mountains are visible in the distance.