 They are the only surviving Gnostics from antiquity.Their religion has been practised primarily around the lower Karun, Euphrates and Tigris and the rivers that surround the Shatt-al-Arab waterway, part of southern Iraq and Khuzestan Province in Iran.Mandaeanism is still practiced in small numbers, in parts of southern Iraq and the Iranian province of Khuzestan, and there are thought to be between 60,000 and 70,000 Mandaeans worldwide.