Geograph - photograph every grid square

Bournemouth: postbox № BH1 21, Old Christchurch Road

Although this box has an Elizabeth II cipher, I have a feeling that it refers only to the front section and that the box itself is older, perhaps Victorian. Younger boxes usually have the slot incorporated into the door rather than above it, and modern double-aperture boxes tend to have two front-panel doors rather than doors on either end.