Vicky Pattison, Rita Simons, and Shane Lynch will take part in the next series of 'Pilgrimage'.
The trio will be joined on the three-part 'Pilgrimage: The Road through Portugal' by Su Pollard, Bobby Seagull, Nabil Abdulrashid, and Millie Knight, with the group, who have different faiths and beliefs, embarking on a personal journey along the northern route of the Fatima Way.
For the first time ever, the group are on a deadline as they need to arrive at the Sanctuary in the city of Fatima - where three local children experienced apparitions of the Virgin Mary in 1917 - in time for a major celebration, which ends with a candlelit vigil attended by almost 70,000 pilgrims from around the world.
As they travel 364km in 15 days, the group will take shelter in pilgrim hostels, a basic campsite and even a working fire station, while they will visit various places on the way, including Bom Jesus do Monte, and a closed order of nuns, as well as sampling other faiths.
Agnostic Vicky is looking forward to learning about different faiths.
She said: “I've never used the word pilgrimage in my life. I don't think I know what this means but as you get older, your life becomes smaller and that's okay, but you can quickly become stagnant, and I don't want to be stagnant.
"I want to constantly be growing and evolving and becoming better. I think by challenging myself and by getting out of my comfort zone, that's when I can broaden my horizons.
"I know there'll be some differing viewpoints, some faiths I'm not familiar with, some opinions that are probably different to mine, but I think the key to us all getting along is just understanding.”
Boyzone singer Shane is seeking "clarity" in his life.
He said: “I am a Pentecostal Born Again Christian. My relationship with God is very tight and I love it.
"The reason why I'm taking on this pilgrimage is just to find a bit of clarity in my life. I want to put myself into a position that I've never experienced before and hopefully find out some amazing and emotional things, so this pilgrimage for me is all about the knowledge I can gather, and about my God. This will be big walk for sure, for many reasons.”
And former 'EastEnders' star Rita hopes to learn more about her own Jewish heritage.
She admitted: “I'm not entirely sure how comfortable I am about revealing to the Jewish community how little I practice the religion. I do think it's very important to know who you are, regardless of how people may judge you and I am comfortable at 45 with who I am.”
Of the other contestants, 'Hi-De-Hi' veteran Su was raised Church of England, while Paralympian skier Millie is a non-practising member of the same church. Maths whizz Bobby is a practising Catholic, and comedian Nabil is a practising Muslim.
The three-part series will air on BBC2 this spring.
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