At the further end of leafy place Dauphine, one of the city’s most appealing squares, looms the huge facade of the Palais de Justice, which swallowed up the palace that was home to the French kings until Étienne Marcel’s bloody revolt in 1358 frightened them off to the greater security of the Louvre. A survivor of the old complex is the magnificent Sainte-Chapelle, built by Louis IX between 1242 and 1248 to house a collection of holy relics, including Christ’s crown of thorns and a fragment of the True Cross, bought at extortionate rates from the bankrupt empire of Byzantium. Though much restored, the chapel remains one of the finest achievements of French High Gothic. Its most radical feature is its seeming fragility – created by reducing the structural masonry to a minimum to make way for a huge expanse of exquisite stained glass. The impression inside is of being enclosed within the wings of a myriad brilliant butterflies.