Mispronounce it when they speak Spanish or mispronounce it when they speak English?
I would probably pronounce
Estella with an L sound in English as I want to be understood and not show off my Spanish. This is actually a personal pet peeve of mine - people who pronounce for example
Volkswagen or
Skoda in English the way they are pronounced in German or Czech (and if they knew how to produce the letter Š on their keyboard they would probably write it that way in English, too
).
I know that the thread started with a discussion of common misspellings on the forum but has branched out into how to write and pronounce geographical words for locations of foreign countries in English. It is a minefield.
So, for writing in
English:
Camino Francés or
Camino Frances?
Navarra or
Navarre? I always write
Navarra although I know that it ought to be
Navarre in English.
O Cebreiro or
Cebrero or
El Cebrero? And while we are at it:
La Coruña or
A Coruña or just
Coruña?
Sevilla or
Seville?
As to
Santiago de Compostela: You don't have to cut some extra slack for non-native speakers of English but have some mercy for the multilingual writers who are used to seeing the name of the town in Galicia correctly written with two ll in
Saint-Jacques-de-Compostelle (French),
Santiago de Compostella (Dutch) and of course as
Compostella in Latin on their Compostela document. When they write it with
ll in English we can perhaps coin the term "Albuquerque effect" for this error.
As to the correct pronunciation of
Roncesvalles in English, I have no idea. It is called
Roncevaux in French and that's probably how many people heard the name of this location first pronounced at school in history class or literature class. Even the English Wikipedia article about
Roncesvalles refers to the
Battle of Roncevaux and offers the English spellings of
Roncevaux Pass,
Roncesvalles Pass and
Ronceval Pass for the pass that is called
Puerto de Ibañeta in Spanish.
There is a neighbourhood called Roncesvalles in Toronto, Canada ... click on the loudspeaker icon in the English Wikipedia article about
Roncesvalles, Toronto to hear how it is pronounced in English.