We would like to go to some of the castles that Rick recommends in his books. We are in our 70's. What tour companies have you used successfully to visit Konopiste, Krivoklat, Kunta Hora, Karlstejn, etc ? I already know about the Yellow Bus to Cesky Krumlov. We figured we could do that one on our own. I have read that sometimes the bus guide's English is not fluent or the castle tour guides either. Did the tours give you enough time or did you feel rushed and would have liked to see more?