Aschau easily can be reached by car as it'is located close to the highway A8 München (Munich) – Salzburg. You can take either the exit Frasdorf or Bernau, depending from which direction you arrive, and after a few kilometres you'll reach Aschau.
Aschau has a little train station. InterCity trains that travel between München (Munich) and Salzburg stop in Prien and from there trains go about each hour to Aschau, where they end then. From Prien it’s about 15 minutes by train to Aschau. You can check for timetables at www.bahn.de.
When you travel back and don't have a ticket yet, please note that at the train station there's only a ticket machine for regional tickets. For long-distance tickets you can go to the travel agency nearby – which has closed Wednesday afternoon, as we noticed!