The Fort can be visited
FortressBlaye
Citadelle de Blaye
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:Cit_Blaye_porte_Dauphine_2.JPG?uselang=fr
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 45.1293, -0.6664