The geographical location of the Baux Plateau on the top of a hill has always given the local people the dual advantage of being able to observe the surrounding countryside and to protect themselves. This no doubt explains why the site was occupied from so early in prehistoric times and has continued to be so right up to the present day.

The earliest known texts, dating from the 10th century, mention 'Balcium Castrum'. They give the name of the local lord as Pons the Younger; his descendents take the surname, Les Baux. During a major building programme introduced by Lords Hugues and Barral des Baux in the 13th century, the early fortress was replaced by a keep that took advantage of the natural configuration of the rock and became a support for the other buildings in the castle.