ELORA, Ont. -- A young man is in critical condition after tumbling down the Elora Gorge.

Police say the 20-year-old was among a group of four hiking on Monday afternoon.

They say the group had climbed about 20 metres from a river bed when they realized they were on private property in Elora, Ont.

As they tried to get down again, the man slipped and fell to the bottom.

Firefighters needed ropes and a stretcher to get him out.

He was flown by air ambulance to Toronto.