Black Esk
The Black Esk is a tributary of the River Esk; one of the two rivers to unite to form the Esk itself, the other being the White Esk.
The Black Esk rises amongs the Ettrick Hills, on the slopes of Jock's Shoulder. The river flows at once southwards until swallowed up buy the Black Esk Reservoir.
The river emerges from the foot of the dam and continues determinedly southward until Sandyford, where it is crossed by the B723 road.
Shortly below Sandyford, the Black Esk turns sharply east then southeast through the Castle O'er Forest. It passes the ancient site of Castle O'er if not the current village, and soon meets the White Esk; from here the united waters are the River Esk.