When something is ravaged, it's ruined. A terrible fire could leave behind nothing but the ravaged remains of your house and possessions.
Use the adjective ravaged when you describe something that's been wrecked, especially in a violent way. War tends to leave ravaged cities behind, and even a high wind can result in a ravaged back yard, strewn with tree branches. The French root of ravaged is ravager, "lay waste or devastate," which comes from the Old French ravage, "destroy," or most commonly, "destroy by flood."