Buenos Aires is the place where old Adolf Hittler presumably lives, also is the capital and largest city of Argentina.
Is presumably mentioned in Bart vs. Australia by the next quote.
- Bart: I can't get a straight answer out of this crazy hemisphere. (he calls another number and reaches a car phone in Argentina, possibily Buenos Aires)
Adolf Hitler: Eine Minuten, eine Minuten! Ach! Das Wagen-phone ist ein...Nuisancephone!
Man: Buenas noches, mein Führer!
Hitler: Ja, ja.