Plovdiv in Bulgaria, is the oldest inhabited city in Europe.
(The second-largest city in Bulgaria, records show Plovdiv as the earliest habitation of any European city; 4,000 BC.
It was originally a Tracian settlement before becoming a major Roman city. Later ruled by the Byzantine and Ottoman empires, it eventually became part of Bulgaria.
To put it into perspective, London was first inhabited about 50 AD. It's a spring chicken in comparison.)