An interesting subject here. Spain is the only country that prohibits the use of its place-names in Spanish where local versions/names occur. Mostly.
Gerona or Girona? Sangenjo or Sanxenxo? Jávea or Xàbia? The local version often takes precedence, which is a bother if you don’t know that Iruña is another way of saying Pamplona (apparently Pampeluna in English says Wiki) or Elx is Elche.
Or Maó is Mahón.
A few other cities have an English version (we use Seville over Sevilla and Majorca over Mallorca even if we have given up on The Corunna).
Sometimes – in the Basque country at least, they just use both – like Vitoria-Gasteiz (well, officially anyway).
Then there are the English-language newspapers that for some reason don’t have an ‘ñ’ on their keyboards, bringing us the joys of Logrono, Peniscola and Salobrena.
And the seasonal Feliz Ano of course.
Come to think of it, the Catalonians prefer Catalunya to Cataluña (they haven’t used the ñ since 1913).
Spain therefore bends over backwards (mostly) to accommodate regional variants – Lleida for Lérida, Eivissa for Ibiza (I mean, really!) and so on, whereas other countries just use the regular name (imagine the weather forecaster on British TV saying Caerdydd instead of Cardiff or Dùn Èideann for Edinburgh).
However, when the Spanish go abroad, it’s all Londres, Estocolmo, Nueva York and Pekín.
Finally, how about the Galician name for Xibraltar!