Basílica de Nuestra Señora del Pilar Church

Brace yourself for the saintly and the solemn in this great baroque cavern of Catholicism. It was here on 2 January 40 that Santiago (St James the Apostle) is believed by the faithful to have seen the Virgin Mary descend atop a marble pilar (pillar). A chapel was built around the remaining pillar, followed by a series of ever-more-grandiose churches, culminating in the enormous basilica that you see today. Originally designed in 1681 by Felipe Sánchez y Herrera, it was greatly modified in the 18th century by the heavier hand of Ventura Rodríguez; the towers were not finished until the early 20th century. The exterior is another story altogether, its splendid main dome lording over a flurry of 10 mini-domes, each encased in chunky blue, green, yellow and white tiles, creating a kind of rugged Byzantine effect.

The legendary pilar is hidden in the Capilla Santa, inside the east end of the basilica. A tiny oval-shaped portion of the pilar is exposed on the chapel's outer west side. A steady stream of people (with busloads of the faithful arriving at times) line up to brush lips with its polished and seamed cheek, which even popes have air-kissed. Parents also line up from 1.30pm to 2pm and from 6.30pm to 7.30pm to have their babies blessed next to the Virgin. More than the architecture, these symbols of the sacred, and the devotion they inspire in the faithful, are what makes this cathedral special.

Hung from the northeast column of the Capilla Santa are two wickedly slim shells that were lobbed at the church during the civil war. They failed to explode. A miracle, said the faithful; typical Czech munitions, said the more cynical.

The basilica's finest artwork is a 16th-century alabaster altarpiece by Damián Forment. It stands at the outer west wall of the choir. Goya painted La Reina de los Mártires (Mary, Queen of Martyrs) in a cupola above the north aisle, outside the Sacristía de la Virgen.

A lift whisks you most of the way up the north tower (Torre Pilar) from where you climb to a superb viewpoint over the domes and downtown Zaragoza.