The ruins of Fort Buoux immediately came to mind when I saw this week's theme - ruin. I decided to not go with the action of ruining something but instead show a photo of ruins.
Fort Buoux is near Apt. It is located on a high rocky outcrop overlooking the valley below which makes it the perfect location for a fort. It had been used since the Roman times and served as a refuge in the Middle Ages. In 1660, Louis XIV ordered it destroyed and it has been abandoned every since. The coolest item was the hidden stairs which provided a secret way to escape if the fort was breached.
Here are some more photos of the ruins.