"Welcome, pilgrim," says the ragged knight in the dirty white cape, thrusting a burning tiki torch into my hand. "You've come just in time."

It is 11 a.m. on Day 26: 558 km into my 780-km walk across Spain on the great medieval pilgrimage route called El Camino de Santiago. The Way of St. James is not a single trail but a cobweb of paths threading through Europe to Santiago de Compostela on the northwestern coast of Spain, where the body of Santiago (St. James the Apostle) is said to have been miraculously discovered in the early 9th century. I've just trudged into Manjarín, a ruined pueblo slowly dissolving back into the misty mountainside, stone by stone. After three weeks of blisters, cramps and tendonitis, I feel about ready to dissolve myself.

That's when I encounter Tomás Martínez de Paz, Manjarín's most prominent (and only) permanent resident and a modern legend on the ancient trail. His thick white cape, emblazoned with the blood-red cross of the medieval Knights Templars, is tied over a camouflage vest. Under his arm he carries a broadsword wrapped in duct tape. When he tells me I'm just in time, I'm hoping he means time for coffee. But Tomás hustles me over to his pilgrim refugio, a derelict pile of granite with almost a whole roof. The yard is decorated like a paramilitary camp for Woodstock survivors. Flags fly over the rubble; across an old satellite dish someone has scrawled bring the soldiers home now! A stack of direction signs — santiago, 222 km; rome, 2,475 km; machu picchu, 9,453 km — lets me know precisely how far I am from nowhere.

Tomás pushes me in front of a harried young couple trying to hold a banner and a squirming little girl at the same time. Still wearing my pack and gripping the tiki torch, I stand at awkward attention while Gregorian chants and hymns of social protest crackle from a cassette player that wanted to give up the ghost long ago. As Tomás clangs a bell with his sword and prays for peace in Iraq, a riptide of delirium washes over me. My knees, calves and ankles seize up. I try not to collapse or set anything on fire.

Tomás, it turns out, once lived an ordinary middle-class subversive's life in Madrid. About 10 years ago, he left his family and proclaimed himself the last of the Knights Templars, the secretive order of medieval warrior monks who protected Christian pilgrims. The Templars disappeared after they were denounced and burned at the stake in 1307, but Tomás has lifted their standard over Manjarín. People can't decide whether to call him a saint or a madman. But if he is a modern-day warrior monk, I could use a little protection.

Let's face it, "pilgrim" is an eccentric title these days. Tomás may be a bit quixotic, but I've got the traditional talismans of a Santiago pilgrim: a scallop shell, a bottle gourd and a walking stick — even if my stick happens to be a telescoping aluminum trekking pole. I've taken my place among the millions of pilgrims who have walked El Camino since the 9th century to pray at the saint's tomb. Over the last 400 years or so, the river of the faithful had slowed to a trickle, but now foot traffic is picking up again, as thousands of people — some propelled by religious fervor, others by a taste for adventure — attempt the Everest of Western pilgrimages. Making the journey today means following a dusty, stony footpath marked by graffiti yellow arrows when most of the world, including good stretches of the original pilgrims' way, has been paved over. It means checking contemporary secularism at the Romanesque church door and learning to go on faith.

But by anybody's standards, I am an unlikely pilgrim. As a food writer and professional hedonist, I spend most of my free time in temples of gastronomy, not tabernacles and certainly not gyms. My idea of adventure is telling the waiter to surprise me. So why am I here? I confess that I began my pilgrimage with an impure motive: to commit the sin of gluttony by eating my way across Spain, then walking it off. Camino purists preach culinary self-denial, but it's not for me. The trail runs through the most delicious landscapes in Spain: Basque country, garlanded with piquant red pimientos hung out to dry; the Rioja vineyards, where I imagined myself feasting on sun-sweetened grapes and spitting out the seeds as I walked; Castilla, with its tender milk-fed lamb and roast suckling pigs; and the final reward of Galicia, with its glorious shellfish feasts starring scallops, the symbol of Santiago himself. Other pilgrims carried lists of recommended refugios; I carried a list of must-eat restaurants.

Day 1, 0 km — St-Jean-Pied-de-Port
Of the myriad routes that make up El Camino, I've taken the road most traveled, the Camino Francés. It leads out of the pretty French Basque hamlet of St-Jean-Pied-de-Port through the lopsided, crumbling medieval town gate called the Porte d'Espagne, then climbs almost a mile above sea level to cross the Pyrenees and the border into Spain. As if the ghosts of Charlemagne, Roland and Hemingway aren't enough, the road is lined with the graves of pilgrims who didn't make it.

Much of the landscape is wild, but it isn't wilderness. Although in the next month I will find myself trapped with running bulls, brush fires and a lecherous small-town mayor, my pilgrimage is not a medieval survival test. Most nights there will be a roof and bed, even if it is just floor space with 80 sweating snorers. There might be a shower curtain in the coed bathroom, or even, when I really need it, a good hotel. As much as I might like to play the adventurer, I'll do little epic battling against the elements — unless you count walking into León on the shoulder of a highway in a blinding thunderstorm, dodging trucks and lightning. These days El Camino is more of a sanity test: the proverbial 40 days of wandering the spiritual wilderness, listening to your internal soundtrack. You discover that losing your mind isn't necessarily a bad thing. The first lesson a pilgrim learns is that most of the baggage we carry is useless.

Day 1, 23 km — Roncesvalles
A 10-year-old British pilgrim boy with a pedometer figures out that it will take me about 1.1 million steps to get to Santiago. I spend a good percentage of those million steps wondering if I'm an authentic pilgrim. Although I'm walking the same road as the medieval pilgrims, I'm in awe of them. How can I try to walk even a mile in their sandals when I'm wearing €250 waterproof hiking boots? They set off for Santiago not knowing whether they would make it back alive, braving highway robbers, disease, miserable food and worse weather. No credit cards, no one-way flights home. They were assured of nothing but suffering and salvation.