Fall due to the state of the trail, way-keeper liability under section 1319a ABGB.
If the fall rests on the defective state of the trail, the way-keeper liability under section 1319a ABGB comes into consideration. The trail is legally a way, so the keeper is liable for the defective state only with gross negligence. Decisive is a specific, recognisable and avoidable defect, for instance an unsecured obstacle in the track.
Next steps: photograph the defect and the spot, secure witnesses and have the gross negligence of the trail keeper assessed.