Cesky Krumlov

Great place, exactly the small town Europe we all crave! Top of my list. If you are traveling with a car be sure to visit the nearby (40km?) Hluboka Castle. The castle is undoubtedly one of the most beautiful chateaus in Bohemia.

Lisa
What a question! This city is one of the UN World Heritage sites, so there must be something special about it. It is a perfectly preserved medieval city set along the Vltava River and dominated by the Schwarzenberg castle (tours available). In the past 20 years the town has undergone preservation and restoration on a great scale. Recreational activities always were a major draw (boating, swimming, camping, hiking) in that region of the Sumava/Böhmerwald, but after the German-speaking population was expelled after WW2, and the border became part of the Iron Curtain, it was left to Czechs to explore.
No longer - Cesky Krumlov/Krumau is just one of the many castle towns in Southern Bohemia, and you can structure an entire trip around it. I suggest you visit the websites for such towns to gain a better understanding of their attraction for others.

The poster is correct - Hluboka (nad Vahom) is another must-see castle. Built in the late 1800s along the lines of English castles, it now serves as a gallery and museum. The white structure is located a little west of Ceske Budejovice/Budweis, and it's an easy side trip if coming to that major city (with a city center that has its own charm).

"Hluboka Castle history: the original royal castle was built by Premysl Otakar II, the founder of Budweis, in the second half of the 13th century. It was rebuilt at the end of the 16th century by the Lords of Hradec. It received its present appearance under Count Jan Adam of Schwarzenberg. According to the English Windsor example, architects F. Beer and F. Deworetzky built a Romantic Neo-Gothic chateau, surrounded by a large English park here in the years 1841 to 1871. There is a winter garden and riding-hall where the Southern Bohemian gallery exhibitions have been housed since 1956."