By the 11th century the ancient structure had sunk to at least 3 metres beneath the street level, with its doors and windows blocked, and served as a storage place for goods and water. During this century, an organisation of Amalfitan merchants settled in Jerusalem and acquired the south-west corner of the Hadrianic forum, where they established a pilgrim hospice, complete with a hospital and a church. The new church was erected above the ancient structure, which became its basement and dictated the tri-apsed layout of the entire church. This church was tended to by Benedictine monks. In 1099, Crusader knights injured during the siege of Jerusalem were treated at the hospital and after recovering started here what was to become the Order of Knights of the Hospital of Saint John of Jerusalem, named after the church, also known as the Knights Hospitaller. After the capture of Jerusalem by Saladin in 1187, the basement was apparently filled with debris.