In 1134, king Louis VI purchased the Merovingian chapel and built on the site the church of Saint-Pierre de Montmartre, still standing. He also founded The Royal Abbey of Montmartre, a monastery of the Benedictine order, whose buildings, gardens and fields occupied most of Montmartre. He also built a small chapel, called the "Martyrium", at the site where it was believed that Saint Denis had been decapitated. It became a popular pilgrimage site. In the 17th century, a priory called "abbaye d'en bas" was built at that site, and in 1686 it was occupied by a community of nuns.