Pilgrimage has been a part of the major faiths for centuries - long and challenging journeys across foreign lands that stretch the faithful and, they hope, bring them closer to God.

In the new three-part series announced by BBC Two this week, Simon Reeve will retrace the adventures of our ancestors and chart what pilgrimage meant to them.

While many medieval Britons believed going on pilgrimage would increase their holiness and chances of getting into Heaven, Reeve discovers a forgotten and more unholy side to pilgrimage.

"The biggest surprise to me was learning about the darker side of holy journeys," he says. "Most of us imagine pilgrimage to be all about piety, blisters and Chaucer, but for many of our ancestors it was their only chance of adventure. There was drinking, sinning and excitement.

Reeve starts his pilgrimage travelling from northern England to Canterbury, then across France and northern Spain, before he treks high into the mighty Alps on his way to Rome.

Finally, he heads east to glorious Istanbul, Turkey, then on to the Holy Land and his final destination, Jerusalem.

Reeve says: "I've been on a few epic trips of my own, but making this series was a chance to learn about the challenges facing travellers in previous centuries as they set out on astonishing adventures trekking around Britain, Europe and further afield, across the world."

On his way, he explores the faith and hope that spurred on medieval Britons, and meets some modern day pilgrims.

"During filming I ate medieval potage in a transport café, played the part of a lovelorn Prince next to a supermarket on the Old Kent Road, camped in the desert, shed a few tears, and climbed high into the Alps. It was a magnificent project to be involved in."

He adds: "I'm not a religious person but I finished filming the series with a new respect for people who made and make these epic trips. I learnt that pilgrimage isn't always a painful and onerous task. It's often a journey of celebration, of adventure, of wonder. I found the whole idea of pilgrimage fascinating and hopefully people watching at home will too."

The series was commissioned by Aaqil Ahmed, the BBC's head of Religion & Ethics, who says: "Simon is the perfect person to take a pilgrimage as he is an experienced traveller with an open mind who can deliver the experience to viewers in an authentic way."

Pilgrimage With Simon Reeve is a co-production between Lion TV and Iridescent Films.