Sisteron's citadel wouldn't look out of place in an episode of Game of Thrones, with its imposing high walls, fortifications and impressive location looking down over the town below.
It's listed as a historical monument and dates back to the thirteenth century. More additions to the original structure were made in the 16th century and again in the mid 19th century.
Sadly it was heavily bombed during WWII, but has since been lovingly restored to its present day glory.
Allow around 2 hours for a visit. It costs around 6-7 euros for entry.
Guided tours are available on request at the tourist office.
