715: runs on the northern bank of the Danube between Krems and Melk.
Buses every hour. Take this bus if you want to visit the Schallaburg.
720: runs on the southern bank of the Danube between Krems and Melk. Buses every one or two hours.
In Krems you get connecting trains to Vienna or the Kamptal
In Melk you can catch express trains to Vienna or Salzburg.
The Campus Shuttle (717) connects the train station Krems and Danube University as well as the Kunstmeile Krems (art district Krems).
722 Spitz - Jauerling - Mühldorf - Spitz. Bus-on-demand call: 0800 22 23 22
723 takes you from Schloss Grafenegg, Krems to Göttweig. Bus-on-demand call: 0800 22 23 22
721 connects the Wachau railway between Emmersdorf and Melk (to the express trains leaving in Melk) and Schallaburg.
For further information see www.vor.at