Judy Dunn, of Aspen, Colo., said she was walking her two dogs on Independence Pass March 23 when 4-year-old Sophie ran off and disappeared, The Aspen Times reported Wednesday.
"I was up there until midnight looking for her," Dunn said, adding she returned at 7:30 a.m. to resume her search.
However, there was no sign of Sophie until Monday morning, when Aspen resident Andre Mpitsos spotted her while walking his own six dogs on the pass.
"About 200 or 300 yards past the gate, I see this little face peering from behind a tree. I said, 'You want a treat?' and she came barreling out," Mpitsos said.
Mpitsos said he recognized Sophie from the missing dog advertisements and fliers around town.
"I was there at the right time, I guess. It was exciting," he said.
Dunn said Sophie lost weight and suffered frostbite to her nose and paws but wasn't seriously injured during her nine days in the cold.