Which mountain in County Mayo is associated with Saint Patrick's Day pilgrimages?

Croagh Patrick in County Mayo is associated with Saint Patrick's Day pilgrimages.

The mountain is traditionally linked to Saint Patrick, who is said to have fasted and prayed there for 40 days during the fifth century. Because of this association, Croagh Patrick became an important pilgrimage destination in Irish Christian tradition.

The largest pilgrimage traditionally occurs on Reek Sunday, the last Sunday in July, rather than on Saint Patrick's Day itself. Many pilgrims climb the mountain barefoot, although practices vary and safety concerns are important on the steep, rocky route.

Croagh Patrick is sometimes confused with Ireland's highest mountain, Carrauntoohil. Croagh Patrick is lower, but its religious and cultural importance comes from its connection with Saint Patrick and the Christianization traditions surrounding him.