Irmela HERZOG
(The Rhineland Commission for Archaeological Monuments and Sites, Bonn, Germany)

Keywords: Historical maps, Lidar data, least-cost analysis

Abstract:
The aim of this contribution is on the one hand to map pre-industrial long distance roads in the study area covering part of the Bergisches Land, Germany, as exactly as possible and on the other hand to assess the accuracy of least-cost approaches that are increasingly applied by archaeologists for prehistoric road reconstruction. The earliest maps covering the study area east of Cologne date back to 1575, 1607, and 1715. These maps are distorted so that rectification is difficult. But it is possible to assess the local accuracy of these maps and to transfer the approximate routes to a GIS. Afterwards road sections coinciding on several historical maps are identified. This historical data is supplemented by the ancient trade route descriptions published by Nicke (2001) who walked in the region and recorded remains of the old roads discussed mainly in local literature. Based on these route reconstructions with limited accuracy, Lidar data is checked to identify remains of these routes. This enables us to map some route sections at high accuracy. The most probable routes resulting from this analysis are compared to the outcomes of least-cost approaches like least-cost-paths and accessibility maps. In regions where the least-cost results coincide with several of the high accuracy road sections, these approaches can also be used to predict missing links. For areas of less convincing least-cost results, the limitations of the methodology are analysed.

Relevance conference | Relevance round table:
The contribution presents a combined analysis of historical and archaeological data applying several GIS approaches.

Innovation:
A methodology combining historical and archaeological data is presented allowing to map pre-industrial long distance roads as exactly as possible.

References:
HERZOG, I. (2013):
Calculating accessibility. In: Earl/Sly/Chrysanthi/Murrieta-Flores/Papadopoulos/Romanowska/Wheatley (eds.): Archaeology in the Digital Era, Volume II. Proceedings of the 40th Annual CAA Conference, 720-734.
NICKE, H. (2001): Vergessene Wege. Das historische Fernwegenetz zwischen Rhein, Weser, Hellweg und Westerwald, seine Schutzanlagen und Knotenpunkte. Nümbrecht.