"Finland is in northern Europe."
Translation:Finland ligger i Nordeuropa.
Well, you can always use södra (southern/the south of) and norra (northern/the north of). It wouldn't be wrong to say "norra Europa" or "norra Norge". If you construct a word like Sydsverige (Söder Sverige is ungrammatical) or Nordeuropa it sounds a bit more specific though, like it's a defined area and not just "the north of". However, this is quite complicated and maybe someone else can explain a rule for this. For example you can't say Söder Sverige as söder is not an adjective but a noun or an adverb that would require a preposition. "Danmark ligger söder om Sverige."