A ripple of applause greeted the first Mass yesterday morning on the summit of Croagh Patrick, Ireland’s holy mountain, as tens of thousands of pilgrims laboured up its treacherous approaches in brilliant and unexpected sunshine.

Rising in a perfect cone on the southern shore of Clew Bay, St Patrick’s Mountain is one of the world’s oldest pilgrimage sites. Its importance as a holy place predates the arrival of Christianity and the national saint’s 40-day fast on its summit.

In recent years this most Catholic of European nations has undergone a rapid process of secularisation, robbing the Church of its once-omnipresent authority and making it vulnerable to attack over a series of sex abuse scandals.

Yesterday the hierarchy was taking comfort from an estimated 40,000 pilgrims who made the 700m (2,510ft) ascent, forming queues at peak times. Among them were hundreds of the “New Irish”, the Eastern European Catholics whose faith is reversing the decline in church congregations across Ireland.

Typical of these pilgrims was Miroslawa Gorecka, a 17-year-old from Katowice living in Galway whose mother came to Ireland to work as a doctor.

“For me life would have no meaning without my Catholic faith,” she said.

“I’m not used to this kind of hardship and it’s good to make a sacrifice.”

Official figures for Ireland’s Polish population hover about 100,000 but the true figure is likely to be twice that. They have been joined in the past decade by Latvians, Lithuanians and others.

Romana and her boyfriend Marek, both aged 26 and from the Czech Republic, are working on a cattle farm in Wexford for the summer. They drove up to westernmost Co Mayo to climb Croagh Patrick not just once but twice.

“We got here on Saturday and thought we should go up while there were not so many people around, but we wouldn’t have missed today either,” said Marek.

Romana said that her interest was kindled by the parallels between Croagh Patrick and Mount Radhosten, near her home town of Roznov, where the Gospel arrived among the Slavs and where a similar pilgrimage takes place ever summer.

A small whitewashed chapel adorns Croagh Patrick’s summit, where Mass was said every half-hour, priests taking turns with the local Archbishop of Tuam, Michael Neary, who climbed the holy mountain in baseball cap and tracksuit.

During his Lenten fast in the year 441, St Patrick is said to have dispelled all the snakes from Ireland by throwing a bell down the mountainside.

The pilgrimage took root soon after that date but in the 12th century was moved to the summer months after 30 pilgrims perished on the mountain during a thunderstorm on the night of March 17, 1113.

That also conveniently put paid to the more ancient celebrations on the mountaintop. For the Celts it was the dwelling place of the deity Crom Dubh and the principal site of the harvest festival of Lughnasa, where women slept the night on the summit in the hope of encouraging fertility.

Yesterday was the 50th consecutive “Reek Sunday”, as the pilgrimage is known, for Father Martin Newell, 76.

“This may sound surprising, since the numbers have started going up again in recent years, but it’s quieter than it used to be.

“When I first came here there would be people walking by torchlight from midnight, but now people come here just to pray more than used to be the case. It’s a fact that Ireland has become more secular, but the more it does the more religious the minority becomes.”

While there were many blasphemous groans of “Jaysus!” and outbursts of encouragement – “C’mon Eamon, keep attackin’ it!” – on the way up, some hardier folk marched barefoot. “It’s something I feel I have to do, it’s only once a year,” said Pat Minnock.

Caroline Noone, from Belmullet, Co Mayo, concurred. “It’s a penance, you offer it up for family and friends, for someone who’s ill. It’s a sacrifice, I’m doing it for the holy souls in Purgatory. The more suffering there is on the way up, the better. You have to suffer.”

Then she laughed and said: “This is my third year. They say that if you do it three times you go straight to Heaven!”

Caroline was walking with Patrick McDonnell, a retired fisherman who spent nearly 30 years in England, where he said he “hoboed every town and village in the land.”

Mr McDonnell, a fluent Irish speaker, appreciated the Gaelic Mass that was said but would not mind if it were joined by services in Polish, which are already being said in increasing numbers of Irish churches.

“I had a visit from the Holy Spirit just here only a few moments ago, it doesn’t matter in what language if all people could experience that just once in their lives.”

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