Sounds like that's what OP did due to multiple trains missing their connections. If you take the ICE, then Munich to Hamburg would be a bit under 6 hours and you wouldn't have to change trains at any time.
Going border to border from Garmisch-Partenkirchen to Flensburg would increase that to ~11 hours due to the regional trains being slower and ~40 mins layovers each in Munich and Hamburg.
655
u/SpareRelation9363 19h ago
People in russia driving for 30 hours just to be still in siberia