Keukenhof is actually in Holland... but it's only a 4 hour drive away.
There are loads of castles in Germany, we prefer the ruined ones with secret tunnels that you can explore, which is what Rheinfels was, but there are others that have been more restored.
What I found fascinating (especially in Heidelberg) was the different parts of the castle that had been built over the years, or other parts that had been destroyed - there was one entire turret that had just collapsed into the moat, mostly intact, and had just been left there!
Comments
There are loads of castles in Germany, we prefer the ruined ones with secret tunnels that you can explore, which is what Rheinfels was, but there are others that have been more restored.
What I found fascinating (especially in Heidelberg) was the different parts of the castle that had been built over the years, or other parts that had been destroyed - there was one entire turret that had just collapsed into the moat, mostly intact, and had just been left there!