The mistake by the MJ - Municipal Journal - was spotted by Public Services Minister Leighton Andrews.
A response to his Twitter message said: "Apologies for the production error. #localgov - not geography - is clearly our strong point!"
Earlier in October a glitch on Google Maps located the Brecon Beacons in the heart of London.
The MJ describes itself as "the UK's leading weekly magazine for council chief executives and their teams of decision-makers in local authorities and allied sectors".
A local government magazine which placed Cardiff in the south west of England has apologised.