Tucked away on Île de la Cité in the Royal Palace, not far from Notre Dame, is a stunning gothic church.
Almost always packed with long queues, Sainte Chapelle is famous for its 12-century stained glass. It's best to check it out on a sunny day as the interior gets flooded with colored light.
It's also in the process of being restored. Ah, well.
Almost every surface is decorated- the floor, the ceiling, the pillars. So much work went into it. It was originally the private chapel of King Louis IX built to house his relics.