Related Clues:

• Enclosure for a budgie, say
• Capital walk can end up miles from Cambridge
• An environment that's very limiting for flight or walk
• A walk from prison to prison
• Where there's little escape from current ebbing through broken bridge
• Aviary
• Small aviary
• One prison after another for chat perhaps behind bars
• One local prison after another for chatterers behind bars
• Walk in London, one with plenty of bars with high-fliers inside
• Fliers' accommodation with bars
• Composers, one heard, providing arrangement of bars for singer
• Where Polly goes for a walk in London
• Walk in London where composer's passed time
• Local prison has bars for a little chat perhaps