Soweit ich mich erinnere, war die Reise lang und langweilig.

English Translation

The journey, as I recall it, was long and tedious.

Langweilig = boring, I haven’t seen it used as tedious. Is this an alternate use?

As a native German speaker, I agree with you that this translation sounds a bit off.

The usual translation of “langweilig” is “boring”.

If you break the word “langweilig” apart into its parts (“lang” and “weilig”) and then translate them literally, the literal translation of “langweilig” is “(taking a) long while”. Thus you can understand why “tedious” was translated with “langweilig”.

However, that is not the best translation in my opinion. “langweilig” is virtually always associated with “boring”. I never heard a German saying “langweilig” for “tedious”. There are much better translations, for example, “langwierig” or “langatmig” (requiring a long breath) if you want to emphasize that it took a long while or “mühsam” or “ermüdend” if you instead want to emphasize how draining/tiresome and how much of an effort it was.