Christina Calayca, 20, of Toronto, went for a jog on the morning of August 6, 2007 in Rainbow Falls Provincial Park, Ontario, where she had been camping with her cousin and two friends from a church group. The park is located around 200 kilmetres east of Thunder Bay.

Calayca and her friends were inexperienced campers. Their first night there, the group had a bonfire and stayed up until around 4 a.m.

The next morning, Calayca and her friend Eddy went jogging around 6:30 a.m. The two split up, and Calayca ran along the trails and Eddy ran along the highway.

Eddy returned to the campsite an hour later, but Calayca never did. She has not been seen since.

The OPP Northwest Region Emergency Response Team had used “four canine units, three helicopters, two fixed-wing aircraft and a float plane” to try to locate her. Approximately 100 police officers and specially-trained civilians searched the area for 17 days. What was at the time considered cutting-edge technology was also used in the search, including GPS mapping software, infrared cameras, and underwater side-scanning radar.

No sign of Calayca has ever been found.