Pros: Great views of Ljubljana, centrally located, cool historic site.
Cons: Pricey for what you get, fairly modernized.
I definitely recommend you visit the castle while in town, as the view alone is very cool. If you're in average physical shape, you should be able to walk up to the castle from town without taking the funicular. The cost of admission basically gets you access to the tower and a video outlining the history of the castle. They're both okay, but not quite sure they justify a 6 Euro entry fee. Oh well, it's a nice contribution any way.
You can still get nice views of the surrounding city without paying the entrance fees and that's probably what I would do if I came back.
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