Related Clues:

• Castle security
• Bob who directed "Cabaret"
• Ditch round castle
• Ship sunk by enemy discovered in trench
• Fortified moat
• Starts dropping acid into enemy trench
• Defensive water
• Castle defence
• Government check closes a defensive construction
• Ditch made the Roman way
• Long trench or ditch
• "Pippin" Tony winner
• Former Tower of London surrounder
• Water around a castle
• Castle's watery defense