The Three Sisters Wilderness is located in Oregon's Willamette National Forest near the town of Sisters and the city of Bend. It is named for the Three Sisters mountain peaks (North, Middle, and South, also known as "Faith", "Hope", and "Charity"). The wilderness area was originally designated in 1964, and consists of 286,708 acres. It is bordered by Mount Washington Wilderness to the north and Waldo Lake Wilderness to the south. The wilderness contains Collier Glacier (the largest in Oregon), as well as some of the best examples of glaciated terrain in the northwestern United States. It includes over 260 miles of trails, including 40 miles of the Pacific Crest Trail.
For more information, visit either the Forest Service or Wilderness.net.