Unusual
article | Reading time5 min
We explain everything you need to know about plan-reliefs, and introduce you to the one of Mont-Dauphin!
What are plan-reliefs?
Relief maps were created in 1668 by Louvois, Minister of War. They provide a three-dimensional representation of strongholds and their surrounding countryside up to the limits of cannon firing ranges (around 600 metres at the time) and the enemy's approach in the event of a siege.
Relief maps represent fortified sites located in frontier zones, on land or by the sea. They enabled Louis XIV and his staff to plan improvements and simulate sieges from Paris, where the collection was located. It was the Google Maps of Louis XIV!
Today, the original relief plan of the stronghold of Mont-Dauphin is kept in the attic of the Musée des Plans-Reliefs des Invalides in Paris. A replica is on display in the Mont-Dauphin arsenal.
Louis XIV never came to Mont-Dauphin, but he was able to visualise the stronghold thanks to this model!
Philippe Berthé - Centre des monuments nationaux
The plan-relief of Mont-Dauphin
Almost four metres across, the relief map of Mont-Dauphin was produced in 1709 and modified at the end of the 17th century. It shows in particular
- the plateaux of Mont-Dauphin and Guillestre ;
- the walls of the stronghold with the two fortified gates and the guardhouses, the redoubt on the northern front (the future lunette d'Arçon) and the glacis;
- the village with the civilian houses and their gardens, the engineer's house, the church ;
- the arsenal, the powder magazine, the three existing barracks and the barracks planned but never built, the existing officers' pavilion and the one still planned, the clock pavilion;
- the layout of the streets and the two roads serving the stronghold;
- the torrents: the Guil and the Chagne;
- the farms in the village of Eygliers;
- cultivated fields, vineyards, a diversion canal and mills.
Philippe Berthé - Centre des monuments nationaux
The relief map: a mine of information about Mont-Dauphin
Located in the arsenal and forming part of the visitor trail, the plan-relief of Mont-Dauphin is an exceptional tool for understanding Vauban's project and the history of Mont-Dauphin.
In 1713, the Treaty of Utrecht shifted the borderline: Mont-Dauphin was no longer in the front line and its development was to slow considerably. The plan-relief, produced in 1709, sets out the desired design for Mont-Dauphin and includes features that were never built (barracks, officers' pavilion, housing blocks, etc.).
The plan-relief also bears witness to the development of Mont-Dauphin's architecture, including the 17th century gunpowder magazine and its English courtyard (a building covered in earth in the 19th century), and the Rochambeau barracks with its artillery terrace (also with a Philibert Delorme-style framework in the 19th century).
Philippe Berthé - Centre des monuments nationaux
How were relief maps made?
To produce the relief plans, engineers and topographers were first called in. They carried out field and topographical surveys. Carpenters, modellers and artists then transformed the data into models. Produced on site, the relief plans were then transported to Paris and preserved in the Louvre and then the Invalides.
From the two-dimensional plan and the topographical surveys, it was then possible to produce a three-dimensional model.
- Surveying techniques
The entire collection of relief maps is on a scale of 1:600 (1 foot for 100 toises according to the measurements of the time). The topographical surveys consisted of several thousand landmarks (orientation) and measurements (distance, height). The instruments used included compasses, squares, protractors, toises and measuring chains.
The plan-relief of Mont-Dauphin is 3.42 metres long and 2.90 metres wide.
- The materials used
The relief maps are large jigsaw puzzles made up of wooden tables, the upper part of which is carved and modelled to recreate the relief.
The rocks, first carved in wood, are finished with a paste made from papier-mâché of different colours kneaded with starch and fixed with gum arabic.
Fields and meadows are made of silk. Trees are made of silk and interwoven wire. Waterways are painted. Buildings are carved from small blocks of wood and painted or covered with engraved paper.
Philippe Caetano - Centre des monuments nationaux
Where can you see the relief map of Mont-Dauphin?
To admire the copy of the plan-relief of Mont-Dauphin, you can take the guided tour of the fortifications and discover the amazing history of this fortified village designed by Vauban.
You can find all the tour times in the diary.
What about the original plan-relief of Mont-Dauphin? You can see it at the Musée des Plans-Reliefs, during certain temporary exhibitions.
