A
- A1 Pit: TL198701
- Abbots Ripton: TL235780
- Abbots Ripton (Hall Farm): TL242781
- Abbotsley: TL230565
- Abington Pigots: TL306445
- Adams Road Sanctuary (Cambridge): TL436588
- Addenbrooke's Site: TL465552
- Adventurers Fen - See Wicken Fen (Adventurers Fen)
- Ailsworth: TL120990
- Ailsworth Heath - See Castor Hanglands
- Alconbury: TL188758
- Alconbury Airfield: TL210765
- Alconbury Weston: TL180770
- Aldreth: TL445733
- Alwalton: TL135958
- Anglesey Abbey: TL534622
- Archer's Wood: TL175810
- Arrington: TL325505
- Ash Wood: TL138662
- Ashley: TL698615
- Ashton: TF103058
- Aversley Wood: TL165820