"By the 5th century, the Roman Empire was in rapid decline and in AD 410, the Roman occupation of Britannia came to an end. Following this, the Roman city also went into rapid decline and by the end of the 5th century was practically abandoned."
A list of "oldest cities" which contains places like Canbera and Detroit, but not places like London and Venice, seems very odd
There was a story a couple of weeks ago[0] about pottery dating from around 3600BCE being found at a site in Shoreditch (which was being excavated for the new Amazon HQ), suggesting London may have been inhabited considerably longer than previously thought.
[0] https://www.mola.org.uk/blog/largest-group-early-neolithic-p... & https://www.nature.com/articles/s41586-020-2178-z