Josquin wrote: As has already been mentioned, "reisen" is upper register and corresponds to the English verb "to travel".
Aha, I think you have now explained another class-tutor correction (other than the one we talked about elsewhere, and actually a different tutor...).
I used this once to talk about going on holiday (a "normal" holiday, nothing special about it), and was surprised to be corrected. Either I didn't quite understand the reason for correction, or I have forgotten (or both), but I think I see now.
As it happens, I think we sometimes use "travel" in English in a fairly everyday sense (e.g. "Oh, I'm going up to Newcastle today..." "Right...how are you travelling?" "Oh, I'll get the train..."), and at other times it does have more of an "upper register" feel, e.g. a "world-traveller", "to travel hopefully is better than to arrive...", (and snobs might prefer to think of themselves as "travellers" rather than "tourists").
But it sounds like there is more of a distinction in German.
I would of course love to think of myself as being able to speak in upper register German, but then one has to be able to do it consistently, and also to know when it is appropriate, and when not.