@4meAndyou it's actually commemorating 900 years of Textus Roffensis. The Rochester book. Which is the earliest written English book and contains laws laid down by Alfred the Great, Cnut etc and the Kent kings.
The words on the wings are from the text and the dragon is inspired by some of the illustrations in the text.
Magna Carta is only 800 years old. The castle opposite played its part in the Baron's revolt. The Rochester siege being one of King John's bloodier episodes.
You can't see the rear corner that was mined during the siege unfortunately.
