In 2014-2016 the Finnish-Swedish Archaeological Project in Mesopotamia (FSAPM) initiated a pilot study of an unexplored area in the Tūr Abdin region in Northern Mesopotamia (present-day Mardin Province in southeastern Turkey). FSAPM is reliant on satellite image data sources for prospecting, identifying, recording, and mapping largely unknown archaeological sites as well as studying their landscapes in the region. The purpose is to record and document sites in this endangered area for saving its cultural heritage. The sites in question consist of fortified architectural remains in an ancient border zone between the Graeco-Roman/Byzantine world and Parthia/Persia. The location of the archaeological sites in the terrain and the visible archaeological remains, as well as their dimensions and sizes were determined from the ortorectified satellite images, which also provided coordinates. In addition, field documentation was carried out in situ with photographs and notes. The prospecting of sites in the Ṭūr ’Abdīn satellite imagery surpassed many of the expectations. In the first directory of archaeological sites identified, 40 % are new and previously unknown, which is a small token of the huge research potential still hidden in northern Mesopotamia. Some variation appeared in the number of sites in each of the arbitrarily defined regions, and their characters appear to be quite different, too. The project has located new, important archaeological remains of the Roman military presence on the eastern border against Persia in late antiquity, and had also been able to suggest new border arrangements.