Related Clues:

• What my castle's drawbridge covers
• The castle's crocodiles may be in it
• Water surrounding a castle
• What a drawbridge crosses
• Watery castle defense
• Bad place to swim near a castle
• Protector with a drawbridge over it
• Trench around a fortress
• Guard seen around a castle
• Many old assault threats initially — prevented by this?
• One goes round castle, treading nothing into carpet
• The castle's crocodiles live here
• Ditch surrounding a castle
• Advantage that keeps competitors at bay, in business lingo
• Aquatic protection