Umayyad Mosque mosque was built on the site of a Christian basilica dedicated to John the Baptist, which was earlier a Temple of Jupiter converted into a cathedral by the Roman emperor Theodosius I Umayyad Mosque in Damascus; built on the site of a Christian basilica dedicated to John the Baptist (Yahya), which was earlier, a Roman Pagan temple of Jupiter. Great Mosque of al-Nuri in Homs; initially a pagan temple for the sun god ("El-Gabal"), then converted into a church dedicated to Saint John the Baptist Great Mosque of Hama; a temple to worship the Roman god Jupiter, later it became a church during the Byzantine era Great Mosque of Aleppo; the agora of the Hellenistic period, which later became the garden for the Cathedral of Saint Helena