A bit of research on Google revealed that this ad for Abbots Lager was painted near Tobruk, Libya, in January 1941 by the 6th Division of the Australian Army.  (‘Journey to Tobruk: John Murray – Bushman, Soldier, Survivor’ by Louise Austin).

My father wrote under the photo:  ‘Australian beer is best’.

Abbots Lager sign painted by 6th Division, AIF, 1941

366 unusual things: days 44-48 Weekly photo challenge: Down