1959 Map of Three Sisters

About this map

South Sister and Middle Sister dominate this high-altitude landscape of the Cascade Range, which is defined by massive lava flows and numerous volcanic features. At the time of this late-1950s survey, the area was largely accessible by a network of trails, including the Oregon Skyline Trail and Obsidian Trail, reflecting its development as a managed wilderness under the Willamette National Forest and Deschutes National Forest. The map documents a system of recreational infrastructure and mountain lookouts, such as Sunshine Shelter and the Scott Mtn VABM Lookout. Geologic markers like Rock Mesa and the wide Wickiup Plain illustrate the complex volcanic history of the region. Scattered seasonal sites such as Knobs Sheep Camp and several forest camps indicate the specialized land use in this high-desert-to-mountain transition during the mid-20th century.