Sainte-Chapelle, Paris

Sainte-Chapelle is a royal chapel built to shelter Louis IX’s remarkable collection of Passion relics, including the Crown of Thorns. Its great windows are now the building’s defining treasure: an immense surviving ensemble of medieval stained glass. Construction began in 1245, and the chapel was consecrated on 26 April 1248.

Pierre de Montreuil is identified as its architect, and its design belongs to the Rayonnant Gothic style. Look at the tall glazed surfaces and the slender stone framework: they make the chapel feel less like a heavy enclosure than a jewel-like reliquary. The building originally formed part of the Palais de la Cité, the royal residence, and its two levels served different communities: the royal household used the chapel above, while courtiers, servants, and soldiers worshipped below.

The relics themselves were later transferred to Notre-Dame. After damage during the French Revolution, the chapel underwent a major restoration in the nineteenth century. It remains one of the surviving buildings of the Capetian palace, alongside the Conciergerie, and its luminous windows carry the strongest memory of the purpose for which this extraordinary chapel was made.