Day trip to Cesky Krumlov from somewhere in Austria?

The reference library of a city near you may have the Thomas Cook European Timetable. The map on page 472 shows your lines. Cesky Ktumlov is 31 kilometers up the Vltava valley from Ceske Budejovoce (CB). You reach CB from Salzburg or Linz via Summerau or from Vienna via Gmund. In both cases a day is not really long enough, but here goes. When your train reaches CB you cross under the road to the bus station, as busses are faster and more frequent than trains for this route, and bring you to a city gate.

Vienna Franz Josephs Bahnhof 0705, Gmund 0921 to 0926, Ceske Budejovice 1023
Ceske Budejovice 1652, Gmund 1829 to 1842 Vienna 2056. 6 ? hours 9in CB, so 4 ? hours in Ceske Krumlov.
Salzburg 0436, train with couchette car, Ceske Budejovice 0834
Salzburg 0600, buffet car train, Linz 0712, 0735, Summerau 0842 to 0851, Ceske Budejovice 1003
Ceske Budejovice 1812, Summerau 1922 to 1932, Linz 2045 to 2109, buffet car train, Salzburg 2217
Ceske Budejovice 2032, train with couchette car, Salzburg 0042

The four hour journey from Salzburg (or shorter from Linz) with no change of train, is best choice, so long as you book yourselves to sleep in couchettes (bunk beds) each way, at a 10 euro supplement each way. That way you have 12 hours in Cesky Budejovice, or 9 hours in CK (please do not miss the last bus back).

ben.haines@btinternet.com