at present unidentified (now identified, see update below). I think the photo dates from the 1930s (based on the other photos it is with), and the location is somewhere in the UK. I have just been looking at lighthouses trying to identify it, but haven't found it yet. I did wonder if it were the Lizard Lighthouse (seen from a different angle to the photo on the link), but I'm not 100% convinced. If you know where it is, please leave a comment, thanks :).