This research project was concerned with ancient measurement data mostly, but not exclusively, distances. The primary aim was to collect, visualize and evaluate specifications of distance that have been handed down in ancient texts.


A database created by research group (C-5) Common Sense Geography comprises of more than nine thousand entries from more than a hundred ancient authors and texts. Among them are nearly all Greek and Roman geographers (e.g. Strabo, Ptolemy, Itinerarium Antonini), most of the historians (e.g. Herodotus, Cassius Dio, Procopius) and several other texts from the Archaic till the late antique times, with some additional material from other pre-modern cultures such as Armenia (Młonač‛ap‛ac‛, Ašxarhac‛oyc‛) and Meso-America (Lienzo Seler). This database is a unique and important research tool for identifying and locating ancient cities and sites or for evaluating ancient measurement data, e.g. the distances transmitted in the geographical works of Strabo and Ptolemy or on Roman mile-stones.

The export function of the data base offers this project the option to visualize the Greek and Roman routes and streets in Google Earth, to convert the ancient units of measurements (e.g. stadion, Roman mile, leuga, parasang, schoenus, day´s journey etc.) into modern units of length and, finally, to compare and check the transmitted data with the accurate distances.

The second goal of this project was to analyze the data with reference to a range of research questions, especially regarding standardization and normalization, as well as measurement operations that were used in practice. In addition, promising is a newly developed mathematical approach to recalculate Ptolemy´s coordinates “back” to the original terrestrial distances and to identify the sources, i.e. the itineraria and periploi used in Ptolemy´s Geographical Handbook. This approach was carried out in collaboration with the mathematician and astronomer Irina Tupikova (Lohrmann Observatory of Technische Universität Dresden & Max Planck Institute for the History of Science, Berlin), a former fellow at Topoi.


Finally, by contextualizing the data (e.g. who handed down what data when, and to what end?), building blocks crucial to the construction of “common sense geography” has been produced and made available to other Topoi research groups and the public. Already some chapters and articles on important issues have been published, e.g. on Strabo´s measurement data or on Herodotus’ use of measurement unit.

Klaus Geus and Kurt Guckelsberger, “Measurement data in Strabo´s Geography”, in: Daniela Dueck, Brill Companion to Strabo, Leiden 2017, 165-177. 

Klaus Geus and Irina Tupikova, “The location of Novaesium: A new interpretation of Ptolemy’s coordinates“, in: Orbis Terrarum 12 (2014, published 2016), 293-309.

Klaus Geus, “A “Day´s Journey” in Herodotus´ Histories”, in: Klaus Geus and Martin Thiering (Eds.), Features of Common Sense Geography: Implicit knowledge structures in ancient geographical texts, Wien 2014, 147-156.

The members of the research project were also working on a GIS model of routes and streets in the ancient Mediterranean. In contrast to already existing models on the internet (like ORBIS, The digital atlas of the Roman world, à la carte, AWMC), this model is not only based on archaeological artefacts but also on the measure data attested in literary sources.

Up to now, the members and fellows of this research project have authored two monographs and a dozen papers and articles, thus underlining the fruitful approach of combining proven and tested methods of classical philology with mathematical and metrological expertise and cutting-edge digital software.