According to tradition the founding of the town came about through two 9th-century pilgrims to the Holy Land, Arcanus and Giles, who returned to the region and built a chapel dedicated to Saint Leonard—whose ruins now lie underneath the current Cathedral of Sansepolcro—where they established a monastic way of life. They had brought a stone from the Church of the Holy Sepulcher in Jerusalem (thus, "San Sepolcro") with them from that shrine which led to the name of the monastery, as it became a popular pilgrimage site. It soon grew to become the Benedictine Abbey of Sansepolcro (the "Badia"). The monastery was declared an abbey nullius.