It is and always will be COLOMBIA!!!! Columbia is a city in the USA, and British Columbia, I believe, is in Canada. Colombia is a large and very beautiful country in South America....many great cities....Bogota. Medellin, Cartagena, Cali, and Santa Marta, just to name a few.
Regarding pronunciation, how often do we hear the word "Escalator" pronounced as "Esculator"? Annoys the hell out of me!
Many well-known radio presenters guilty of this.