A charity swim was aborted after the support boat broke down and hit rocky shores.
The man swimming a section of Loch Ness got out of the water and the RNLI were called when the engine of the support boat failed.
He had been undertaking a swim, run and cycle challenge to raise funds for Drummond School in Inverness.
The swimmer and two others were stranded on board as the vessel drifted onto rocky shores near Abriachan Nurseries on the west side of the loch.
A volunteer crew from RNLI Loch Ness launched the Atlantic 75 Class lifeboat from Drumnadrochit after being alerted to the incident.
A spokesman for the RNLI described the conditions as "challenging" with waves reaching a height of 1.5 metres from peak to trough.
The swimmer did not require medical attention and the boat was towed to the slipway at the Dores Inn on the east side of the loch.
Neill Stebbings from RNLI Loch Ness lifeboat said: "The skipper of the boat did exactly the right thing in calling for help as soon as it was clear that the engine would not restart."