Pilgrim's progress

Even in our godless age, spiritual journeys are as important as they were six hundred years ago, whe

This year, six centuries after Chaucer wrote The Canterbury Tales, about a ragbag of pilgrims travelling to Canterbury from London, Canterbury Cathedral celebrates its 1,400th birthday. And even in our godless age, it is still an important place of pilgrimage. During 2002, as George Carey makes way for a new archbishop, the 104th since St Augustine, two million people will travel to the cathedral he founded way back in 602AD. Not all of them will be Anglicans. Some of them aren't even Christians. But they will all be following in the footsteps of Chaucer's pilgrims. And last month, so did I.

You might think that it's pushing it a bit to call all of these people pilgrims but, back in Chaucer's day, a pilgrimage was a pretty down-to-earth affair, not so different, in fact, from today's package holidays - a bit of culture and quiet reflection but a lot more good clean (or even bad unclean) fun. No wonder medieval Puritans (the Lollards, for instance) looked down their pious noses at pilgrims. Because, although the destination of Chaucer's travellers is the shrine of St Thomas a Becket, the archbishop murdered in Canterbury Cathedral on the orders of Henry II in 1170, the informal tales they tell en route reflect the more prosaic preoccupations of their age. The Canterbury Tales was the first great literary work written and printed in everyday English, and the language we read and write today is shaped by Chaucer's pen.

Chaucer's pilgrims set off from the Tabard Inn in Southwark, a hotchpotch of palaces and brothels on the south side of London Bridge. Modern Southwark is more mundane, and the Tabard is now buried beneath Guy's Hospital, but Chaucer would recognise Southwark Cathedral, where his friend and fellow poet John Gower is buried, beside the Thames. From here, it is 60 miles to Canterbury, straight down the old Roman road that Chaucer called Watling Street, and we call the A2. It is the same route that Graham Swift's old soaks follow in his Booker Prize-winning Last Orders, a book (and film) which proves that even the most secular of men are still driven to pursue spiritual journeys, as they carry their old friend's ashes from the city to the sea.

Chaucer would not recognise much of the inner-city stretch of Swift's Watling Street, a bleak urban thoroughfare pitted with second-hand car showrooms and drive-through burger bars. The only place he might know is St Thomas a Watering, along the Old Kent Road. Where pilgrims bound for the shrine of St Thomas once watered their thirsty horses, run-down Georgian mansions face off high-rise council flats across a municipal boating lake.

Yet as the city opens up into suburbia, he would feel on firmer ground. Chaucer knew Greenwich, where he held down a dreary civil service day job overseeing local dykes and drains, and Blackheath, site of Black Death plague pits and the Peasants' Revolt. Chaucer lived through both catastrophes. Those revolting peasants set off from Dartford, now on the ragged edge of London, where the house of their martyred leader, Wat Tyler, is now a roadside pub. At the end of Dartford's busy high street stands Holy Trinity, already an old church in Chaucer's day. Its faded fresco of St George slaying the dragon, plastered over during the Reformation, cost 15 shillings to paint and £13k to restore. This was where Chaucer's pilgrims spent their first night, but I was on a push-bike, not horseback, and so I panted on via Gravesend to Rochester, the site of England's second cathedral, built in 604, and the shrine of St William, a devout baker from Perth who was murdered here by robbers on his way to Jerusalem. Watling Street was plagued by bandits, and pilgrims travelled in packs as much for safety as conversation.

Rochester's ruined castle was already old in Chaucer's time - it was besieged by Bad King John in 1215, more than 100 years before Chaucer was born - and as the tidy dormitory towns of commuter-belt Kent are finally defeated by scruffy countryside, even older relics rise out of this rural hinterland. Milton Regis, in an industrial corner of Sittingbourne, dates back to the reign of Alfred the Great. Its church was founded in 680. The Saxon queen Sexburga is buried here, and the garden that surrounds its medieval courthouse is dedicated to a more recent royal martyr, Diana, Princess of Wales. Faversham Abbey, built in Chaucer's time, holds the bones of King Stephen and Empress Matilda, warring grandchildren of William the Conqueror. Chaucer's pilgrims spent their third night at the Maison Dieu, an almshouse at Ospringe, just down the road. It's still there today. A few miles further east, in a field beside the Roman road, are the ruins of Britain's only church to have been converted from a Roman temple, already a thousand years old when Chaucer came this way.

Another pilgrim who came this way was Henry II, who travelled here to make penance for uttering the awful oath that prompted Thomas a Becket's murder - "Who will rid me of this turbulent priest?" At the leper colony of Upper Harbledown, a few miles from Canterbury, he got off his horse and walked the last few miles to Becket's shrine. Henry's Norman chapel is still here, a new bypass has left the old Roman road almost as quiet as Henry would have found it, and there, at the bottom of the hill, is the same cathedral he would have seen. At St Dunstan's church, outside the city wall, King Henry took off his shoes, and walked barefoot into Canterbury.

Becket's bones were burned by Henry VIII, but the empty space he left behind is more striking than any shrine. An adjoining chapel commemorates more modern martyrs, from as far afield as Alabama, San Salvador, Uganda and Auschwitz, where a priest called Maximilian Kolbe took the place of a fellow prisoner who had been condemned to death. A simple stone marks the spot where Becket was slain; and it was here, in 1982, that Robert Runcie, then archbishop of Canterbury, and Pope John Paul II knelt and prayed together.

Such crucial acts of heroism and reconciliation make Canterbury Cathedral a vital place, both within a Christian context and without. But are The Canterbury Tales equally relevant today? Terry Jones certainly thinks so. Most famous from Monty Python, he is also an eminent medieval scholar, whose ground-breaking book Chaucer's Knight (Methuen) transforms our cosy image of the poet, revealing him as an ironic satirist, mocking mercenary knights and clerics who debase the old ideals of chivalry and piety, rather than the grand old man of English literature who praised the rustic virtues of his age. "It's almost like having a tape recorder from 600 years ago," Jones tells me. "You can hear the people talking."

Jones is currently writing a book called Who Murdered Chaucer?, which portrays Chaucer as a writer far more political than we have previously been led to believe. "He disrupts social hierarchies," argues Jones. "He's actually very subversive." As a civil servant, Chaucer depended on the patronage of Richard II. When Richard was deposed by Henry IV, Arundel, Henry's archbishop, began a campaign against heresy. "It's just like Bush now declaring war on terrorism - the reason he does it is to get the country behind him." This transformed Chaucer's irreverent religious critique into a politically explosive tract. "These are very radical charges, very sensitive areas - particularly as he was writing in English," says Jones. Henry seized the throne in 1399. Chaucer died in 1400, within months of Richard's murder. "There's no will. There's no tombstone. There's no record of what happens to him. He just disappears."

Whatever happened to Chaucer, Jones's scholarship shows that, centuries after his death, Chaucer is still important for the eternal truths he tells us about human nature, which remain unaffected by the transformations we have wreaked upon his world. "What is so great about history and about Chaucer is to see that people are just the same," says Jones. "Humanity doesn't really change." And you don't have to be a medievalist, or a Christian, to follow the pilgrim trail to Canterbury, and celebrate the 1,400th birthday of a cathedral that was already 800 years old when Chaucer died.