All of these are official cities and all are compact. St David's (in Wales) has a population of about 1,800, Wells (in England) about 10,500, Armagh (N. Ireland) about 15,000 and Stirling (Scotland) is a giant among pygmies at around 36,000. The 10 smallest UK cities according to their population in the latest census are:

  1. St David's (1,797) Wales
  2. St Asaph (3,491) Wales
  3. City of London (7,185) England
  4. Wells (10,406) England
  5. Bangor (13,725) Wales
  6. Armagh (14,590) Northern Ireland
  7. Ely (15,102) England
  8. Ripon (15,922) England
  9. Truro (17,431) England
  10. Chichester (23,731) England

More Info: en.wikipedia.org