Not the precise date MartinR, but it might not be as early as it first looks. The terrace of houses on the right going up the hill were constructed after 1873 (1st Ed. OS), but before 1898 (2nd Ed. OS). The buildings in the right foreground are still shown on the 1938 OS map, but are gone by 1958. At a guess, I would say just pre WWII, but it could be just after?