Here are a few suggestions for your next trip from Straßberg(Harz)

In 5 hours, you can reach Berlin, Dresden, Nürnberg.

In 6 hours, you can reach Hamburg, Munich, Frankfurt am Main, Dortmund, Bremen.

In 7 hours, you can reach Köln, Stuttgart, Düsseldorf, Strasbourg, Szczecin, Ústí nad Labem, Essen, Enschede.

In 8 hours, you can reach Prague, Basel, Utrecht, Liège, Liberec, Poznań, Salzburg, Innsbruck, Most, Arnhem.