Karlovy Vary is a small mountain spa town in the Bohemian Hills, and has been a popular place to take the waters for generations of Czechs. A good rule of thumb I use for visiting spa towns is to say that if its good enough for the royals, its just about OK for me. Happily for Karlovy Vary, the famous Hapsburg family of Austria have been regular visitors to the spa over the years, and if you want to be wrapped up in seaweed, and whipped with birch twigs for a day, then there is no higher recommendation than their patronage.
