According to the Boulder County Sheriff's Office, Patricia Wallace was hiking in the area of Buchannan Pass Trail with a group of friends when she decided to take a different route alone. She told friends she believed the route would be easier to trek.
When Wallace could not be found, rescues crews began a search into the night and continued all day Wednesday. More than 10 search teams are currently on the field.
Wallace is described as 5 feet, 5 inches, 135 pounds with dark brown hair and hazel eyes.
Wallace was last seen wearing a white "floppy" hat and hiking clothes. She was also carrying trekking poles.
Officials say Wallace could possibly be suffering from early stages of dementia.
If anyone comes into contact or sees a person matching the description in the area of where Wallace was last seen, contact the Boulder County Sheriff's Office at 303-441-4444.
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