The centuries' old Reek Sunday pilgrimage up Croagh Patrick has been cancelled due to bad weather.
The challenging climb to the 2,510ft/765m summit was called off early this morning after heavy rains and strong winds swept in overnight.
Archbishop of Tuam Michael Neary had been due to celebrate mass at St Patrick's Oratory at the summit at 10.30am.
Gardai issued advice for the thousands planning to make the ascent not to travel due to adverse weather conditions.
Pilgrims have climbed Croagh Patrick - Ireland's holy mountain - for about 1,000 years following in the footsteps of St Patrick who, according to the church, spent 40 days and nights fasting on the summit in 441AD
Thousands traditionally make the ascent on the last Sunday in July, many beginning as early as 2am or 3am and some upholding the practice of walking and scrambling in bare feet.
Wind was gusting to gale force seven between 4am and 5am today, Mayo Mountain Rescue said, with conditions several hours later still regarded as dangerous.
It is believed the organised element of the annual pilgrimage has never been called off before.
Archbishop Neary told RTE: "It's disappointing that the pilgrimage has been cancelled.
"I'm not aware of it having been cancelled before and I've been climbing this mountain since I was a young lad many, many years ago."
While the mountain cannot officially be closed or pilgrims barred from climbing, authorities including Mayo Mountain Rescue are strongly advising people do not make the attempt.
A spokeswoman said: "It is unfortunate but we have to issue this advice in the interests of public safety.
"It is disappointing for people who have made plans but our advice is that it's too dangerous, there are too many people, it's a very poor surface near the top underfoot, it is raining and visibility is zero."
A medical tent set up on the mountain by Mayo Mountain Rescue was badly damaged as the heavy winds and rain swept in overnight.
Hundreds of people were continuing to make the climb despite the appeal.
A number of pilgrims were stretchered off the summit suffering various stages of hypothermia.
