PORCARO, France  The inhabitants of Brittany, on Europe’s rain-soaked western edge, are said to love the church as much as they love a party. Which perhaps makes this tiny Breton village a less improbable locale for the wholly improbable happening it hosts each year.

The festival of the Madonna of the Bikers, which organizers promote as the largest motorcycle “pilgrimage” in France  there are few aspirants to the title  attracted nearly 10,000 motorcyclists from across Europe last weekend to the soggy wheat fields of Porcaro, population 650. It was an unlikely mix of what Roman Catholic Bretons call the “sacred and profane”; many came to pray, many to carouse, a surprising number to do both.

There were priests and incense and holy water and much solemnity and prayer, but also AC/DC and studded leather, body piercings and tattoos and, beginning well before noon and lasting well into the night, the consumption of prodigious quantities of alcohol.

“No one should leave here without having gotten what he really wanted out of it,” intoned the Rev. Jean-François Audrain, presiding over an open-air Sunday Mass. Draped in white gilded vestments, he addressed a crowd of thousands of bikers and local faithful, gathered in a rolling field behind Porcaro’s 19th-century stone church. Later, he joined four fellow priests in sprinkling holy water on thousands of rumbling Harleys, Hondas, Ducatis and Kawasakis, filing past one by one.