The ancient city of Karkemish is located on the western bank of the Euphrates near the frontier between Turkey and Syria. Georeferencing the site is a crucial phase for a good integration of the different available datasets, thus, topographic fieldwork was realized integrating classical surveys made by total station with GNSS measurements. The GNSS observations acquired in several days in September 2012 were processed and combined in a unique solution in the ITRF 2008 international reference system. A digital terrain model of the area was also generated, by a real time kinematic survey. The present work was performed in the framework of a Turco-Italian project, in a multidisciplinary perspective.