In the area to the west of the town of Siena, on the charming Camporegio hill, dominating the Fontebranda upland plain - with its renowned, monumental fountain - rises the majestic basilica of S. Domenico. Erected in 1226, in Gothic style, by the Dominicans, and enlarged in the fourteenth century, the basilica, finished in 1465, was restructured again in the sixteenth century. The imposing brick-built construction, its unfinished fašade dating from the original design, is flanked by an elegant campanile with crenellation dating from 1340 (lowered in the eighteenth century), displays clear Cistercian influence in its grandiose rectangular apse, stretching with its heavy walls towards the Fontebranda valley. The vast, solemn interior, built to an Egyptian Cross plan, with a single nave, lit by light from elegant twin-light windows, contains interesting works of art associated to the life of St. Catherine of Siena, the town's patron saint: a famous fresco of the saint, believed to be the only faithful portrait of her, painted by Andrea Vanni, and an equally notable painting, by Mattia Preti in 1672, depicting her canonisation, to be found in the suggestive Chapel of the Vaults, there is also the chapel entirely dedicated to St. Catherine, in which a marble tabernacle, a fine fifteenth-century work by Giovanni di Stefano, contains the reliquiae of the saint's head, and a fine pictorial cycle - including the outstanding Ecstasy and Fainting of St. Catherine, a Sodoma masterpiece - narrating episodes from her life. At the high altar are the noteworthy, refined ciborium and two sculpted marble angels, the 1475 work of Benedetto da Maiano and, in one of the chapels of the left transept, admirably adorned with stucco work and frescoes, an enthroned Saint Barbara among angels and the Sainst Magdalene and Catherine, a fifteenth-century masterpiece by Matteo di Giovanni. From the end of the nave a stairway leads down to the monumental crypt - which can also be entered from the left side of the church - built at the end of the fourteenth century and spaced by robust columns and which is divided into three grandiose naves. To the right of the building is the lovely fifteenth-century cloister of St. Domenic, rebuilt in the twentieth century.