Whats in a name:

One story sugests the town got its name from the many bridges that crossed over the river Medway in the town. There were 5 streams in the town so the name Tonbridge shortened from the word “Town of Bridges” Town of Bridges

Tonbridge was recorded in the Domesday Book 1087 as Tonebrige, It may indicate a bridge belonging to the estate or manor (from the Old English tun), or alternatively a bridge belonging to Tunna, a common Anglo-Saxon man’s name.
The 'Tonbridge' name, in the late 1800's was actually known as Tunbridge, old maps prior to this date show it as such. In the late 1890's/early 1900's this was changed by the Royal Mail as it caused confusion with Tunbridge Wells a much more recent town. The latter has always spelt its name that way.
1782 Map

Not Tunbridge Wells
Tunbridge wells was always known as the Wells near Tunbridge then the springs were discovered in 1606 then in 1909 King Edward VII recognised the town because of the springs and gave the town its official "Royal" title Royal Tunbridge Wells but Tonbridge is the older town.
If you look around the town on old buildings you can see different spellings of the name Tonbridge
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