Details of plans for the ascent of Croagh Patrick by Archbishop Seán Brady of Armagh this weekend were released yesterday.
Dr Brady will lead the annual pilgrimage, starting out on the climb at 7am on Sunday and then preside at concelebrated Mass on the summit (2,510ft/ 764m).
It will be the first time that an archbishop of Armagh has climbed the mountain since St Patrick, the Catholic Communications Office said.
Up to 30,000 people are expected to climb the mountain. Croagh Patrick attracts over 100,000 visitors annually.
Archbishop Michael Neary of Tuam has dedicated this year's pilgrimage to immigrants who have made Ireland their new home.
Westport Town Council will hold a civic reception tomorrow in honour of Dr Brady at the Civic Offices, Altamount Street. The reception will be hosted by the the council's cathaoirleach, Cllr Teresa McGuire.
Later, Dr Brady will be the chief celebrant at the vigil Mass and the homily will be delivered by Dr Neary.
At 7am on Sunday, Dr Brady and Dr Neary will start the climb from the car-park in Murrisk.
Besides the concelebrated Eucharist on the summit, Mass will also be celebrated every half-hour from 8am to 2pm, with liturgy in Irish at 10am and 11.30am
Those intending to climb are asked to bring good footwear, suitable clothing, a stick and water, and to be mindful of the safety of themselves and other pilgrims.