In 1942, three teams of workers spent 8 months, day and night, building a half-buried bunker as a bomb shelter for several hundred. In one of the rooms, all the telephone lines connected the commander in chief General Gerd Von Rundstedt to the Atlantic front.
On June 6th 1944 it was from this West front German forces communication centre that, Von Rundstedt unsuccessfully attempted confrontation of the allies in Normandy.

Another bunker was built in the centre of the « Cité Médicis », where the majority of the houses had been requisitioned by the Germans.

The bunkers of Saint Germain en Laye:

-    Park of the Castle of Saint Germain en Laye
-    The Médicis City  | Rue Thiers
-    Pavillon Henri IV | below the hotel
-    Gramont district | Rue Saint Louis
-    25 bis rue Alexandre Dumas
-    Villa David | Rue Alexandre Dumas
-    Marcel Roby school | Two on the grounds
-    Rue Félicien David | the shelter of Von Rundstedt’s headquarters, invisible from the street
-    4 rue Félicien David | shooting position on the outside sidewalk
-    13 rue des Monts-Grevets | gun turret in the garden
-    6 bis boulevard Victor Hugo | visible from the Rue Bellevue
-    13 boulevard Victor Hugo | at the moment it is a garage
-    10 ter boulevard Victor Hugo | shelter under the greenery

Today, for security reasons, access to the bunkers is prohibited.