Saint-Gilles is the second most populous commune in the Nîmes metropolitan area.

The Benedictine abbey of Saint-Gilles was founded during the seventh century traditionally by the hermit Saint Giles whose relics the abbey possessed. The commune formed around the nucleus of the abbey, which was the first stopping point for pilgrims bound for Santiago de Compostela in Spain, who were following the via Tolosana that led from Arles to Toulouse and crossed the Pyrenees to join other routes at Puente La Reina, thence to Santiago along the Via Compostelana. The former abbey church was listed in 1998 among the UNESCO World Heritage Sites, as part of the Routes of Santiago de Compostela in France. The abbey church's west portal is among the most beautiful of the great Romanesque portals and a definitive example of the Provençal Romanesque. The church has three naves and a famed spiral staircase of cantilevered stone steps (in the now destroyed part of the church). During the French Wars of Religion the Protestants fortified themselves within the abbey, which was severely damaged.

The shrine of Saint Gilles, located in the crypt of the church, is the subject of pilgrimage in particular by women wishing to become pregnant or dealing with infertility.