Answer by Ian Sawyer:
Not only the longest place name in the UK (North Wales to be more specific) but the proud possessor of the longest internet domain name in the world –But it's hardly a city, a large village might be more appropriate, having a population of around 3,000 people.
The village was originally called Llanfair Pwllgwyngyll, which means 'The Mary Church by the pool near the White Hazels', however the village was renamed in the 19th century as a marketing ploy to attract visitors at the time the railways were expanding across the UK, and previously less accessible regions were opened up to tourists. The station is on the train line from London and the Midlands to Holyhead, a major port for crossing the Irish sea to Dublin in the Irish Republic.
The village is signposted as just Llanfairpwllgwyngyll, and is known locally as Llanfairpwll or simply Llanfair. P.G.
This is the local railway station sign, with a helpful pronunciation guide under the name: