In archaeological surveys and excavations, positioning and mapping of sites and monuments is essential to studies related to settlement pattern, viewshed analysis as well as cultural resource management. Various methods and techniques have been used in the past for the mapping of sites according to the technological means that were available at each time. These methods had a variable degree of accuracy, creating a number of problems in the repositioning of archaeological sites today. The errors and inaccuracies of the past mapping techniques are discussed and they are compared with the latest developments of the GPS technology. The various GPS geodetic surveying techniques employed today are here addressed, along with a statistical analysis of the position data, as a function of time and distance. Problems related to the transformation of geodetic coordinates from one reference system to another and the geometric registration of aerial and satellite imagery are addressed, as well as the effects of error propagation in the analysis of viewshed or topographic slope.