In 2000, the OEAI began a new research project, "The Topography of the Upper City of Ephesos." The area of the Upper City, the south-easternmost part of the ancient city of Ephesos, has until today never been the focus of systematic, archaeological inquiry and urbanistic considerations, leaving out sporadic investigations in the late 19th and the 20th centuries.
The goal of the archaeological investigation of this area is to obtain a picture of the archaeological substance of this area using all of the modern means available to us today which conserve and protect the finds.
The archaeological inventory comprises the analysis of historical sources and aerial photography, a terrestrial inventory using GPS (Global Positioning System), archaeological mapping (survey) as well as geophysical prospection. This multiplicity of information flows into the geographic information system (GIS), which manages, generates, and evaluates the widely differing data. The results of the field work, tied in to the historical context, ought to open up a new, expanded picture of the extremely complex urban history of Ephesos.

Up until 2005, in cooperation with Archeo Prospections®, 8 ha. of the area have been geophysically prospected using radar, and 26.3 ha. have been magnetically geophysically prospected. The prospected data provide information about the street grid and the internal construction of individual building blocks. The survey areas outside the city wall - whose course around the Upper City has been verified for the first time - have allowed new insights into the extra-urban development, the cemeteries, and the course of the streets in the direction of Magnesia on the Meander. During the course of the archaeological survey a total of 55,000 points were measured covering an area of 228 ha., and thereby over 7,000 archaeological structures were mapped and photographed. In 2003, in cooperation with the Institute for Cultural History of Antiquity of the Austrian Academy of Sciences (S. Ladstätter), an intensive artifact survey, covering an area of 2.5 ha., took place in the middle of the most densely developed area of the Upper City. The enormous recovery of finds in the inner-city area, and the extremely large distribution - chronologically as well as in terms of amounts of material - represented numerous challenges for the methods to be employed. The interpretation of the data from the artifact survey, together with the information already obtained from the extensive GPS-survey as well as the geophysical measurements, were put into a GIS. The combination of surface and sub-surface data allowed conclusions regarding the pattern of building and its chronological distribution inside the city area.
As a result of this work, today a completely new picture of this part of the city can be presented: in the Upper City of Ephesos, a residential area existed on a 50 ha. large plateau lying between the two city hills of Panayirdağ and Bülbüldağ In the course of the Hellenistic city development, the area was opened up with a checker-board pattern of streets and buildings, consisting of 7 streets oriented east-west and 24 oriented north-south. The street grid followed the topographical conditions, whereby an effort was clearly made to use the existing building land as efficiently as possible. 88 building blocks (insulae) were embedded into this orthogonal street grid, while the Upper Agora (the so-called State Agora) took up four of these insulae. The individual insulae were parceled up, whereby today numerous peristyle houses can be identified. Regularly arranged plazas, water conduits, and drainage systems attest to the infrastructural opening up of the Upper City, whose grid of streets remained fundamentally unaltered from the Hellenistic up until the Byzantine period.