A kayak accident at a Rocky Mountain national park has left a young man in critical condition.

The man, in his early 20s, was kayaking with a small group in Yoho National Park on Monday when he overturned and hit a rock.

He was knocked unconscious and help was called. The man was airlifted first to Golden and then taken to a Calgary hospital.

The man was kayaking at Wapta Falls, the highest volume waterfall in the park, which is 30 metres at its highest point. The park is on the B.C.-Alberta border.