Many accurate 1921 census transcriptions have already been added to the pub history site, including London, and parts of Middlesex. If you can contribute to the site, send me some details to Kevan, along with some description of the specific property.
Here is the history of Pubs in Cambridge A - F ; Cambridge G - P ; Cambridge Q - Z
Babraham Balsham Barrington Barton Bassingbourn Benwick BoroughGreen Bottisham Bourn Boxworth Brinkley Burwell
Caldecot Cambridge (3 indexes) Carlton CastleCamps Caxton Chatteris CherryHinton Chesterton Cheveley Chippenham Christchurch Coates Comberton Conington Coton Cottenham Coveney Croydon
Doddington Downham DryDrayton Dullingham Duxford
Eastree Elm Elsworth Eltisley Ely
FenDitton FenDrayton Fordham Fowlmere Foxton FridayBridge Fulbourn
Gamlingay Girton Gorefield Grantchester Graveley GreatAbington GreatEversden GreatShelford GreatWilbraham GuildenMorden Guyhirm
Haddenham Hardwick Harlton Harston Haslingfield HatleyStGeorge Hauxton Hinxton Histon Horningsea Horseheath
Landbeach Leverington Linton Litlington LittleAbington LittleEversden LittleGransden LittleShelford LittleWilbraham Littleport Lode LongStanton Longstowe
Madingley Manea March Melbourn Meldreth Mepal Milton
Oakington Orwell Over Pampisford PapworthEverard Peterborough (Northants before 1965) Prickwillow
Sawston Shepreth ShudyCamps SixMileBottom Snailwell Soham Stapleford SteepleMorden Stetchworth StowcumQuy Stretham Sutton SwaffhamBulbeck SwaffhamPrior Swavesey
Teversham Thetford Thorney Thriplow Toft Trumpington TyddStGiles
Waterbeach WelchesDam WestWickham WestWratting WestonColville Whittlesea Whittlesford Wicken Wilburton Willingham Wimblington Wisbech Wisbech St Mary Witcham Witchford WoodDitton