In terms of chronology one striking observation is the almost complete lack of evidence for any other periods than the Edomite (7th–6th century BC) and the Nabataean (1st century BC – 1st c. CE) periods. While the city centre and surrounding areas have evidence for occupation and structures for the Roman, the Byzantine and the Medieval periods, no traces whatsoever of these periods were found on top of Umm al-Biyara, with the exception of a very small number of African Red Slip wares and some Medieval sherds of the so-called Ayyubid-Mamluk type On Medieval pottery from the Petra area see now the concise overview by Sinibaldi 2009. . Also, there was no evidence of occupation in the period between c. 500 BC and the 1st century BC At Busayra, for example, the Iron Age occupation continued to c. 300/200 BC – see Bienkowski 2002 – but there is no such evidence of later Iron Age and early Hellenistic occupation on Umm al-Biyara so far. . The survey further clearly revealed a concentration of activities during the Nabataean period focussed on the eastern ridge of the plateau, i. e. the part of the summit that offers the best view towards the city centre while at the same time being the best visible from the surrounding area, especially the city centre. These are the sectors of the plateau densely occupied by monumental buildings (fig. 3). However, the collected pottery shows that during the Nabataean period the areas towards the NW part of the plateau must also have seen some activities although no visible remains survived on the surface. Compared to the British survey of 1965 we were able to identify many more structures and to correct the position of some previously mapped structures (cf. fig. 2 with fig. 3). In total 30 structures were reported and mapped, eight being cisterns and their connected water channels, 19 being substantial buildings. For the time being, until proper excavation is undertaken, it cannot be decided in all cases whether we are dealing with individual structures or whether some or even all of them belong to one overall structure. At the very least the common orientation of structures 17 to 20 or structures 15 and 16 etc. might indicate an overall building plan.
It is not the aim of this preliminary report to describe at length every structure. We will focus on some specific ones to provide an initial insight into the Nabataean occupation of Umm al-Biyara.
