Crépy-en-Valois
The castrum didn't stop developing since then: firstly under the impetus of the Counts of Amiens Valois, who founded the Abbey Saint Arnoul in 1008, then with the Counts of Vermandois, particularly Philip d'Alsace and his wife Elizabeth who founded in 1182 in the suburbs a collegiate dedicated to Thomas Becket, archbishop of Canterbury, who was assassinated in his cathedral.