The idea of an invasion from France was present in the minds of the winning military rank of the Civil War almost from the same moment at which the conflict finalized. In September of 1940 already first plans existed to fortify the Eastern Pyrenees. The objective was to fortify the frontier to avoid a possible attack that could bring the Republican Government back. Few months later, in the middle of World War II, the international events gave a turn. In the interview that Franco and Hitler maintained in Hendaye (South-West of France), Franco heard about Hitler's plans to invade the Soviet Union. Then, Franco thought that the opening of that front could take the Germans to the defeat and began to prepare itself for a possible invasion of the allies from France.
In Girona province this defensive system is known as the Linea Gutierrez, due to the second last name of one of the military engineers who participated in their design. In 1943, the year of the German defeat in Stalingrad, the fortification plans were revitalized, and the following year most of the bunkers were already in the process of being built.
The project of the Pyrenean Line divided the fortification in a total of 169 nucleuses, the also called centres of resistance that would be formed by 60 to 80 bunkers, connected one to each other by trenches or tunnels, protected by wire fences and, in some cases, minefields. Each centre of resistance was supposed to have enough room to place between 400 and 500 people, which elevates to 70,000 the number of soldiers in charge to defend this barrier against an enemy invasion. Nevertheless, the line remained unfinished, and the predicted troops never got prepared for it.
It is easy to find those bunkers all around the Alt Empordà, in the coast and in most of the roads near the frontier with France. They are completely abandoned, although some of them are used as a shelter for the excursionists. In the Baix Empordà there are still some bunkers built by the Republicans before the area was occupied by the Franquists.