Pessac is one of the cities ( Bordeaux , Pessac , Talence , Gradignan ) where the Univerity of Bordeaux stands , on one of the bigest campuses in Europe . Pessac is located in the south of the Bordeaux metro area and is surrounded by Bordeaux , Talence , Gradignan , CanÃ jan , Cestas , Saint-Jean-d ` Illac et MÃ rignac .