GESORIACUM BONONIA (Boulogne), Pas de Calais , France.

In the Belgica province of Gaul. The history of the city that grew up around the two sites is characterized by the alternation of the names Bononia and Gesoriacum, as the city's center of gravity shifted from one place to the other.

Boulogne ou Boulogne-sur-Mer, Gesoriacum et Bononia (réunies)

Sources Princeton et Imago Mundi