Don’t drive in the park, even if the GPS is showing you the way to the castle – you are not allowed to drive in the park. I know this, because I was the only crazy person driving in a national park, and in my mind was only: “People are walking because they want to experience the park, it seems that I am the only lazy person that wants to drive to the castle”. Well … I was very confused seeing people looking at me. Until a bus stopped, everyone in the bus looked at me and then I knew. Oops.
So the parking is free, you pay for the shuttle to bring you to the castle 1,5 euro one way. Or you just drive there if you dare.
I didn’t visit the castle, I preferred to walk around it. The garden is beautiful, especially if it’s sunny.