 The River Tilt arises from the confluence of the Tarf Water with the Allt Garbh Buidhe at OS grid ref NN 983797 from which point it flows in a southwesterly direction down the fault-aligned Glen Tilt.In the vicinity of Marble Lodge it turns gradually to a more southerly course and flowing under the Bridge of Tilt at Blair Atholl enters the left bank of the Garry.The Tarf Water follows a course from the west to plunge over the Falls of Tarf before joining the Tilt.