Ur-Les Escaldes: have seen it suggested that this is a local-language(s)? rendering of "Ur of the Chaldees", where per Old Testament, Abraham originally came from -- one tends to suspect that this kind of stuff is "folk-etymology", and that the learned scholars of these matters will tell us that the derivation involves other, and more complicated, matters.
The Petit Train Jaune's route would seem to be "big" both on very short; and long-and-convoluted; names. This featured, again, in the International Transport thread of several years ago -- I take particular pleasure, on this section, in Villefranche-Vernet-les-Bains-Fuilla; and Olette-Canaveilles-les-Bains.