Not all post boxes are created equal: we noticed a few years ago that the post box nearest our house has the letters GR on it – while most of the ones in more modern housing developments say ER. And then this week when we were out and about near Nottingham Castle we spotted one that said VR.
These letters relate to the monarch who was reigning at the time the post box was installed – Elizabeth’s had a good long sit on the throne now (since 1952), and so that’s why her post boxes are prevalent. Our GR post box likely means that King George V was running the show when it went in – he became king in 1910 and remained so until 1936, and the houses on our street were built around 1930.
The Victorian post box in this picture must date somewhere between 1837–1901 – a rather large range of dates! I will try to take pictures if I spot any with other monarchs listed on them. Let me know if you see any unusual post boxes in your neck of the woods!