I was born there in 1942 and it was always Belfast, N.I. postal address, before the postcodes came in. Then after that my address at Castlereagh was Belfast 6, when the early codes came in. Down or Antrim was never mentioned. I was also taught in school that Down or Antrim were never part of Belfast or vice verca except before Belfast was founded and local governments came in. If one lives in Belfast you dont pay rates to Antrim or Down councils do you?