Possible Clues:

• Put the lid on a town; that's all it can hold
• Amount that can be held
• The wherewithal to beat a team from Bristol
• Specified role or position
• A city cap has ability to contain
• Ability, volume
• Put the lid on a town for as much as it will hold
• Surpass, for example, Westminster's legal competence
• Job of keeping lid on a large town
• Amount that can be held - skill