When Louis IX acquired a collection of 22 religious relics from Emperor Baudouin II, he decided to build a monumental structure to house them. Within only seven years, from 1241 to 1248, Sainte Chapelle was erected at the heart of Palais de la Cité. The building consisted of two chapels, the upper chapel destined for the royal family and the lower one for their officers. The identity of the architect of the impressive monument remains unknown, though people marvel until today at his masterpiece, especially the beautiful stained-glass panels which decorate the upper chapel. They are arranged in 15 windows and represent 1113 episodes from the Old and New Testament, as well as scenes from the discovery of the relics, their purchase by the French monarch and their arrival in France. Sainte Chapelle was damaged by fire a couple of times until it was completely destroyed in the French Revolution. Eventually, in the middle of the 19th century, the grandiose structure was restored to its original state.