Visualizing Overland Travel, When All Roads Led to Rome
By: Paul Kahn
Tags: Roadmaps, Maps, Roman Empire, History, Data Visualization

A second innovation was integrating the print with a navigation instrument. The portable compass was to be placed on the square at the bottom of the diagram, and an accompanying text provided instructions on how to orient the map using the instrument.

[T]he compass should be placed on the edge of the map, or against the compass-card printed in the center of the bottom border, and the map turned around until the compass directions correspond with the map’s cardinal points. Then both the map and compass are lined up with the two towns. The acht teyl (compass quarter) to which the needle points indicates the direction the traveler should follow. [8]

This combination of the instrument and diagram gave the traveler the heading to the next town. Symbols beside the town name indicated major churches for the religious pilgrim.

Etzlaub’s third innovation was a reproducible color system. The print included written instructions for coloring regions. While no two surviving copies are colored exactly the same, his instructions were to encode the “seven kingdoms and languages bordering [German country] each with its own color” [9].

Detail of the Romweg from the Bayerische StaatsBibliothek collection, showing the route to Rome from Cracow in Poland via Bruno and Vienna. The colors follow Etzlaub’s instructions: “Poland is colored in brown, Bohemia yellow, surrounded by a green forest. Hungary is grass green…” The road leads between the mountains bordering Hungary to the east and Bohemia to the west. Prague is marked by a castle in the center of Bohemia. Berlin is shown on a different route to the north.

In response to the success of the first map, Etzlaub published a second version in 1501, titled “That are the country roads through the Roman Empire from one kingdom to another, which touch Germany, recorded from mile to mile with points.” This map expanded coverage to the east and south, adding hundreds more cities to the network. His image of a road network in the form of a link-node diagram superimposed on coastlines, rivers, and mountains had defined the European world.

Next: On The Road, From the Postal Web to Lincoln Highway

The second part of Transportation examines the relationship between diagrams of the earliest postal networks and the navigation app on our phones today.

Global Information Design: an overview of the series

Global information design embraces the visualizations of both qualitative data such as expressions of social hierarchy, cultural beliefs, and values, and quantitative data, such as economic trends and scientific explanation. We can broaden our view of information design by following the pathways of its intended use. Exploring the history of how we visualize cosmology and timelines, transportation networks and family lineage, is as informative for current data visualization practice as the mastery of programming libraries and cognitive science. Studying examples of information design from many time periods and many cultures helps us understand how we shape patterns of difference into hierarchies and networks to create that chart, story, or graphic from the patterns that connect.

Part 7: Visualizing Overland Travel, When All Roads Led To Rome (this article)

Bibliography

[1] R. J. A. Talbert, Rome’s world: the Peutinger map reconsidered. Cambridge: Cambridge University Press, 2014.

[2] E. Albu, The medieval Peutinger map: imperial Roman revival in a German empire. Cambridge University Press, 2014.

[3] C. Nüssli, “The Tabula Peutingeriana, a Roman Road Map,” Euratlas, 2010. [Online]. Available: https://www.euratlas.net/cartogra/peutinger/. [Accessed: 01-Dec-2019].

[4] C. Jacob, “Ecritures du monde,” in Cartes et figures de la Terre: exposition présentée au Centre Georges Pompidou du 24 mai au 17 novembre 1980, Centre Georges Pompidou, Ed. Paris: Centre Georges Pompidou, Centre de création industrielle, 1980, pp. 104–119.

[5] F. Schnelbögl, “Life and Work of the Nuremberg Cartographer Erhard Etzlaub (†1532),” Imago Mundi, vol. 20, pp. 11–26, 1966.

[6] S. J. Schechner, “These Are Not Your Mother’s Sundials: Or, Time and Astronomy’s Authority,” in The Science of Time 2016, vol. 50, E. F. Arias, L. Combrinck, P. Gabor, C. Hohenkerk, and P. K. Seidelmann, Eds. Cham: Springer International Publishing, 2017, pp. 49–73.

[7] E. Etzlaub, “Das ist der Rom-Weg von meylen zu meylen mit puncten verzeychnet von eyner stat zu der andern durch deutzsche lantt,” Nuremberg, 1500.

[8] B. Englisch, “Erhard Etzlaub’s Projection and Methods of Mapping,” Imago Mundi, vol. 48, pp. 103–123, 1996.

[9] H. Krüger, “Erhard Etzlaub’s ‘Romweg’ Map and Its Dating in the Holy Year of 1500,” Imago Mundi, vol. 8, pp. 17–26, 1951.