The former residence of the Counts of Toulouse, the Château de Beaucaire overlooks the Rhône valley and is built in a strategic location that has been occupied since the 8th century A.D. The château became part of the royal domain when the Languedoc region was annexed by the French crown during the reign of Louis IX in the early 13th century, and was enlarged a number of times, ultimately becoming a powerful fortress. With its distinctive triangular keep, the site was designated as a historic monument in 1846 and classified in 1950, remaining today as one of the largest fortresses in France.
The Château de Beaucaire is located on a rocky spur which presents a number of inaccessible surfaces. The northern wall forms an extension of the rocky cliff and is not accessible from ground level. The outer layer of dressed stone that covers the walls of the monument presents evidence of deterioration and damp patches. The eastern wall is not visible from ground level, because it has become surrounded by very densely packed buildings. The state of preservation of this part of the wall was therefore unknown due to a lack of access.
Aerial photography carried out using a drone has enabled a survey to be carried out of all elevations of the château and the cliff on which it rests, particularly in areas which are inaccessible and not easily visible from the ground. By adjusting the overall 3D model in relation to points measured from ground level with a differential GPS, we have been able to provide a plan and elevations using the official Lambert conic projection used to represent France in mapping.