"cosmopolitan" means that the city (polis) is universal (cosmos).  I have
no doubt that poeple from all over the world end up stuck at the tip of
South America.  Near me, Merced California is one of the most ethnically
diverse towns in the country.  Not exactly where I want to party for New
Year's though.

Cosmopolitan has connotations of "culture" and "class" in common speech
that might or might not be warranted in this case.  But I'd bet most
towns in Argentina are a bit wilder than places I frequent.

Often words translate badly -- particularly words that are basically
identical.  "Sympathy" in English is not the same as "sympatico" in Spanish,
even if the Greek roots are identical.  Most European languages have
the non-English version of "sympathy".

A Uraguayan co-worker was horrified that we would contemplate such a trip.
He feels there are too many places to cross that are downright dangerous
for Americans in busses.  Like Columbia.  He wouldn't consider doing this
even though he's a Sudamericano -- places like Central American jungles
worry him too much.  I guess he doesn't like guerillas up-close-n-personal.

He thought it would be better to go to Brasil, buy a VW bus there and
stay in relatively safer haunts like Brazil, Uraguay and Argentina.

Of course if any of the crazy Europeans try the Cape-to-Cape thing, they
got African, Middle-eastern and East European places to traverse that make
Columbia and Peru look like bastions of American-flag-waving-democracies.

malcolm