Topographical survey in the area of two Christian buildings outside the city walls of Ptolemais (Cyrenaica, Libya)

Abstract

Topographic measurement works in Ptolemais have been conducted by the Polish Archaeological Mission of the Institute of Archaeology of the University of Warsaw since 2002. 1 A multi-layer digital map which integrates various forms of spatial data such as satellite images, aerial photos, terrain models, geophysical maps and vector objects (architectural elements visible on the surface and contours) was prepared as a result of this survey. It was necessary to develop a methodology for fieldwork using GIS techniques, which allowed for proper data processing and later analysis and clear presentation. Measurements and aerial images give the possibility of description, and even partial interpretation or reconstruction of documented objects. This article refers to the extensive documentary work in Ptolemais, focusing on thetwo Christian buildings discovered outside the eastern walls of the city.