Going south along the east side of Derwentwater from Keswick, you will reach a very narrow steep unclassified road to your left signed for Watendlath.
The road, the tiny hamlet and Watendlath Tarn [small lake] are all picturesque and imensely photogenic, as can be seen from the website below and also from http://www.scawdel.co.uk/watendlath.htm