Sisteron

Sisteron guards a narrow passage of the Durance between steep rocks, its citadel rising above the town. A castle was recorded here in the eleventh century, and the site belonged to the counts of Forcalquier in the twelfth. The fortress was reshaped in the late sixteenth century for artillery warfare. After the Duke of Savoy invaded the upper Durance valley in 1692, Vauban designed an extensive plan to strengthen Sisteron, although only part was carried out.