Mariette Forest, 81, from Sherbrooke, Que. was reported missing from a campground in Baddeck Inlet this morning at 10:30 a.m. but was last seen around 8:30 a.m.
RCMP said when Forest was last seen, she was wearing a checkered orange and black jacket, jeans and running shoes. She was also carrying a walking stick. She is described as slightly built, about five feet tall and white.
RCMP Cpl. Scott MacRae said searchers were continuing to look for Forest through the night.
Cape Breton Regional search and rescue, and a crew from Cheticamp are searching in the darkness. Later Wednesday night, crews from Inverness and Straight-Richmond will take over.
McRae said they are continually evaluating their search plans but there are plans to expand the search area in the morning.
Police said she left the Baddeck Cabot Trail Campground to go for a hike on the nature trail.
Ground search and rescue, Department of Natural Resources and a helicopter joined the search earlier in the day, along with water rescue.