Turin Cathedral

The Cappella della Sacra Sindone is a rotunda of black Frabosa marble grafted onto the east end of the cathedral and reached from the choir and from the adjoining Royal Palace, so that the Savoy court and the public could each approach the relic. Guarino Guarini, a Theatine priest and mathematician, took over the unfinished project in 1668 and completed the dome in 1694, stacking six-pointed rings of segmental arches into a cone of light that is one of the boldest structures of the Italian Baroque.

The Shroud was kept in an urn above the central altar. On the night of 11-12 April 1997 a fire, most likely electrical, broke out during preparations for an event; the blaze consumed the chapel and threatened the relic until a fireman, Mario Trematore, smashed the reinforced display case and carried the casket clear. The Shroud survived intact. Restoration of the fire-blackened marble took more than two decades, and the chapel reopened to visitors in 2018. Because the chapel is no longer used to store the cloth, the Shroud is now housed in the cathedral's north transept.

The Shroud is a linen sheet about 4.4 by 1.1 metres bearing a faint, straw-coloured double image of a man, front and back, marked with wounds consistent with scourging, crucifixion and a lance thrust to the side. Its documented history begins in the 1350s at Lirey in France; it passed to the House of Savoy in 1453 and to Turin in 1578. In 1988 three laboratories at Oxford, Zurich and Arizona independently radiocarbon-dated small samples and reported, with high confidence, a date range of about 1260 to 1390, published in Nature in 1989.

Critics have argued the tested corner was a medieval repair or contaminated, and studies of the image chemistry, pollen and weave continue to be published on both sides; none has overturned the radiocarbon result in the mainstream scientific literature. The Catholic Church has never defined the Shroud as authentic. Popes have called it an icon and a mirror of the Gospel and have venerated it while leaving the question of origin to research, a stance the Archdiocese of Turin restates at each ostension.

The cathedral was commissioned by Cardinal Domenico della Rovere and built in white marble to a Tuscan Renaissance design attributed to Meo del Caprino, replacing three older churches dedicated to the Saviour, Saint Mary and Saint John the Baptist that had stood on the site. Completed in 1498, it kept the free-standing bell tower of 1470, later heightened by Filippo Juvarra.

For centuries it was the ceremonial church of the Dukes and later Kings of Savoy, whose capital Turin became, and its fortunes were bound to the dynasty that owned the Shroud. The building is comparatively plain inside, its fame resting almost entirely on the relic and on Guarini's chapel behind the altar. As the metropolitan seat of the Archbishop of Turin it remains an active parish and cathedral, drawing steady visitors and, at the rare ostensions of the Shroud, very large crowds of pilgrims from around the world.