The Put In on the Afon Tryweryn is a designated launch point for whitewater paddlers, located near the raft put-in steps at the National White Water Centre.

It marks the downstream boundary of the 'Top Site' section, which runs from the Welsh Water gate below the stilling basin to this point. Paddlers using this access point must be suitably experienced and properly equipped for whitewater conditions.

Required kit includes a craft appropriate for whitewater, a buoyancy aid meeting ISO 12402-5 or EN393, and a helmet conforming to EN1385. All participants must be capable of self-rescue.