Sentence:  Pliny calls e Tarsus a <WSD>free city</WSD>: which is an incontestable proof it was not a Roman colony, for then he would have called it so. 
Meaning of the word marked with <WSD> tags:  Any of various types of city of Europe from classical to modern times, characterised by relative autonomy and/or being responsible only and directly to a king or emperor; a more modern city of such type, sometimes elsewhere than in Europe.