When modern Paris has overwhelmed you with its boutiques, bicycles, and baguettes, step back in time at two of its most interesting and historical landmarks in medieval Palais de la Cité - once the residence of the Kings of France. Sainte-Chapelle with its mesmerizing stained glass windows was home to Christ's Crown of Thorns, while the Conciergerie was home, or rather _prison_ to Marie-Antoinette!