Resafa – Sergiupolis, the later Rusafat Hisham, is an exemplary site for an exemplary exploration. On the site of a late Roman limes fort (3rd century), a magnificent pilgrimage site to the tomb of St. Sergios (5th/6th century) developed, which was then elevated by the great caliph Hisham to his residence (8th century). On the basis of the research carried out until 2011, a panorama of the transformation is drawn up: Divided into 14 phases of urban development, from the 1st century AD to our own time, this is presented vividly for the first time in the form of a reference work, based on a large number of large-size color maps as well as serial 3D model renderings.