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A 3D-model of the Nasca lines at Palpa (Peru)

The Nasca Lines or geoglyphs in the desert of south Peru are among the most famous cultural heritage sites in the world. Unfortunately, their investigation and interpretation has been hampered for a long time by the lack of an accurate documentation. Based on aerial imagery that was especially acquired for this purpose, we produced a virtual 3D model of the northern part of the Nasca region, around the modern town of Palpa. The slopes and ridges of this area are covered by more than 1’500 geoglyphs that are shown in the model. This 3D model of Palpa, presented at the workshop for the first time in its complete form, is the result of 5 years of archaeological and photogrammetric fieldwork at Palpa jointly conducted by geodetic engineers of ETH Zurich and archaeologists from Germany and Peru. The model consists of a DTM, photorealistic texture based on an orthomosaic, and a vector layer showing the geoglyphs. These high-resolution datasets are needed to ensure accurate results of the intended archaeological analysis. The overall file size of the 3D model is about 3 GB. Such an amount of data could not be visualized in real time until recently when more powerful hardand software became available for PC systems. For the Palpa model we use Skyline by IDC, Switzerland, to visualize the terrain and the geoglyphs. The advantages and shortcomings of this software are discussed in the present paper. Furthermore, the use of the 3D model as a valuable tool for archaeological research is described.