We took a day trip to Krivoklat on a Sunday late in June 2013. It was 377 kc round-trip for two for the fare from Hlavní Nádraží. Note: make sure you take the fast train. We took the local train and it made about 6 stops on the way to Beroun, where you have to take another train to Krivoklat. We defininitely should have paid more attention there.
The small town around the castle is picturesque and idyllic, to say the least. It was 190 kc each to see the "full castle tour". The tour itself is in Czech but they give you a printed paper to follow along. However, the printed notes do not cover the entire tour, so we were just guessing about 3/4 way through. I do still recommend the tour though since you have access to areas of the castle that the public cannot see.
The courtyard of the castle is filled with small shops that sell local handicrafts, and a small cafe. It was a weekend, so I fully expected to see people dressed in medieval outfits doing things, but alas, just an old dude charging 60 kc to shoot a crossbow. Maybe the talent was on strike?
All-in-all, a great country respite from Praha, especially if you're staying for a while. Pro-tip: take the small path up the hill into the little village to check out a beautiful old church, and stay right on your way back down to get the best view of the castle.
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