The Basilica of Saint-Romain in Blaye was an important Merovingian basilica, the resting-place of Charibert II, a son of Clotaire II who was briefly king of Aquitaine from 629 to his death in 632, and of his son. According to the 12th-century Chanson de Roland contained the body and relics of the Carolingian folk-hero Roland, who was a seigneur of Blaye in the eighth century.
The nominal patron of the basilica, belonging to the Canons Regular of Saint Augustine, remained the local 4th-century martyr Saint Romanus of Blaye; here the pilgrims bound for Santiago de Compostela paused before taking to boats to cross to Bordeaux.
In 848, the fort and its surrounding habitations were laid waste by the Viking chief Hasting.
Some vestiges of the structure remain within the Vauban fortress at Blaye, which formed part of the traditional defenses of the Gironde estuary.
References:The Citadelle of Quebec is an active military installation and official residence of both the Canadian monarch and the Governor General of Canada. It is located atop Cap Diamant, adjoining the Plains of Abraham in Quebec City. The citadel is the oldest military building in Canada, and forms part of the fortifications of Quebec City, which is one of only two cities in North America still surrounded by fortifications, the other being Campeche, Mexico.
The first fortifications in Quebec were built by the Governor General of New France Louis de Buade, and completed just in time for the Battle of Quebec in 1690.
After the British conquest in the second half of the 18th century, the problem of Quebec City's defences grew more acute.