Citadel of Besançon - Credit: Wikimedia Commons
The Citadel of Besançon () is a 17th-century fortress in Franche-Comté, France. It is one of the finest masterpieces of military architecture designed by Sébastien Le Prestre de Vauban. The Citadel occupies on Mount Saint-Etienne, one of the seven hills that protect Besançon, the capital of Franche-Comté. Mount Saint-Etienne occupies the neck of an oxbow formed by the river Doubs, giving the site a strategic importance that Julius Caesar recognised as early as 58 BC. The Citadel overlooks the old quarter of the city, which is located within the oxbow, and has views of the city and its surroundings. Read more on Wikipedia
Source: en.wikipedia.org