Guer is a commune in the Morbihan department in Brittany in north-western France.
It is located at the edge of the famous Brocéliande Forest, which is the setting of the Round Table novels in Brittany. It is southwest from Rennes, the regional capital.
Camp Coëtquidan (Camp de Coëtquidan) is located in Guer and comprises three military educational facilities:
- École Spéciale Militaire de Saint-Cyr, France's foremost military academy dedicated to the training of Army officers through direct recruitment
- École militaire interarmes (inter-services military school), for non-commissioned officers
- École Militaire du Corps Technique et Administratif (military school of the technical and administrative corps)