In 1659, Louis XIV takes advantage of the Treaty of the Pyrenees, to annex the occupied territories: Roussillon Vallespir, Conflent, Capcir, and half of Cerdanya. These territories are soon the province of Roussillon.
The border between the kingdoms of France and Spain, which passed over the Corbieres, now passes of the Pyrenees. Salses fortress which protected the old frontier from the Spanish side had no longer any strategic importance.

 

 

 

From 1659 to 1667, Louis XIV was not very interested in defending Roussillon but because of the rebellion of the Angelets in 1669 against the introduction of the salt tax, Villefranche had to be defended.

In fact the rebellion made it obvious that it was important to keep a check on the Vallespir and the Conflent which were open to the plain of Roussillon.

So Louis XIV then decided to provide Roussillon with an effective defence system.

He sent Vauban to the region in 1679 to inspect the defences and he cleared an area at the entry to Cerdagne which he called Mont-Louis. Collioure just needed some improvements to its defences but a fort needed to be built at Villefranche, and at Prats-de-Mollo an engineer suggested that they raise the town walls and enlarge Fort Lagarde. At Bellegarde he designed a vast fortification based on his Spanish project. Further work was also to take place at Port-Vendres.

But his most ambitious project apart from Mont-Louis concerned Perpignan so in 1680 he set about reinforcing the existing fortifications so that the town could be sealed off completely.

However, for geopolitical reasons, not all the projects were finished.

 

The city’s of Mont-Louis and Villefranche de Conflent are two major site built by Vauban and registered on the list of the Unesco World Heritage.
 

See also our heading "What to see and do" to discover Vauban’s buildings in the Pyrenees-Orientals.