People have lived here since the Mesolithic. In 2010, excavators below the Folkestone Roman Villa found worked flints older than agriculture. Above the East Cliff, an Iron Age oppidum produced quern-stones on what archaeologists describe as an almost industrial scale - the stones used for grinding grain into flour, traded across the Channel for continental pottery and wine. A modest Roman villa was built over the Iron Age settlement in the first century AD; a more luxurious one followed around 200 AD, then was abandoned in the third or fourth century for reasons no one knows. The name Folcanstan didn't appear until the late seventh century. Folca's stone, most scholars agree - a marker, probably, for the meeting place of the local hundred, the administrative unit Anglo-Saxons used to organise the countryside. Folca is forgotten. His stone gave its name to a town.

In 630, Eanswythe founded a nunnery on the site of her father's castle, near where the parish church now stands. She refused all offers of marriage. She died around 640 and was made a saint quickly. Her bones were moved into the chancel of the church on 12 September 1138 - the date still celebrated as her feast - and pilgrims came. The religious community grew into a monastery and lasted until Henry VIII dissolved it. Her relics vanished from public knowledge until those Victorian workmen found them in 1885. The town's seal carries her image alongside William Harvey, the seventeenth-century Folkestone-born physician who discovered the circulation of blood - the first person to describe accurately how the heart works as a pump. The town gave the world a saint and an anatomist, four centuries apart, born in roughly the same square mile.

Until 1807, Folkestone was a fishing community whose seafront was constantly battered by storms and shingle. An Act of Parliament that year authorised a proper pier and harbour. Thomas Telford - the engineer behind the Menai Bridge and half of Britain's canals - built it in 1809. By 1820, nineteen acres of harbour had been enclosed. But the Pent Stream kept silting it up, and the Folkestone Harbour Company went bankrupt in 1842. The South Eastern Railway bought the derelict harbour as it was building the London-Dover line. The railway reached Folkestone on 28 June 1843. By the late nineteenth century, the Earl of Radnor had hired the architect Decimus Burton - who had designed parts of Regent's Park - to lay out the western part of town as an elegant coastal resort. The Leas, the broad promenade Burton designed along the clifftop, became a place where Queen Victoria and Edward VII walked. The grand crescents and white-stuccoed hotels still line it. So does the Leas Lift, a Victorian water-balanced funicular that opened in 1885 and still carries passengers down to the beach.

Two world wars and the rise of the package holiday hollowed out the resort. The harbour lost its ferries when the Channel Tunnel opened. The last ferry to Boulogne ran in 2001. For a while Folkestone faded - elegant, slightly threadbare, a coastal town with too many empty hotels. Then the Old High Street, an ancient cobbled slope between the cliffs and the harbour - one of Charles Dickens's favourite streets, by his own account - became the heart of a Creative Quarter. Independent shops, restaurants, working artists' studios. The Harbour Arm, formerly closed to the public, has been restored as a public walkway with bars and food stalls. The closed-down railway viaduct above it has been turned into another promenade. Saga, the insurance and travel company, has its headquarters in town. So does Church and Dwight, which makes Arm & Hammer baking soda for the UK market. Folkestone is no longer fashionable in the Edwardian sense - it is something else now, more interesting, more honest about its history.

On Dover Hill, the highest point of Folkestone, the Anglo-French Survey of 1784-1790 set up a sighting station to measure the precise distance between the Royal Greenwich Observatory and the Paris Observatory - one of the great geodetic achievements of the eighteenth century. The other principal sighting point was Fairlight Down in Sussex. From Dover Hill the surveyors looked east along the Folkestone Turnpike to Dover Castle. Today on Cheriton Hill above the Channel Tunnel terminal, a white horse was cut into the chalk - completed in 2003, the work of the Folkestone White Horse Project, visible from trains crossing into the tunnel. The Battle of Britain Memorial at Capel-le-Ferne, just east of town, commemorates the airmen who fought in 1940 over these cliffs. Folkestone's cliffs are not white like Dover's - they are greensand and gault clay, a different geology entirely, the result of being on the southern edge of the North Downs where it meets the Folkestone Formation. Different stone, different colour, same sea, same view of France.