The private retreat of King Ludwig II, this massive and beautiful estate is the most visited castle in Germany and is the inspiration of fairy-tale movie castles like the one featured in Sleeping Beauty. That's right, this is pretty much the standard on which every Disnified American child has been raised, although seeing it in person may be just the thing to revive in you a sense of childlike wonder.
Built on a Bavarian hilltop, this multi-faceted and elaborate palace is a 30 minute walk from the ticket office at the base of the hill (Ticketcenter Hohenschwangau), although there is public transport provided. During the summer, the walk may be just the activity to build your anticipation, while in the winter the bus will be the practical choice. Tickets are about $17 USD and include a guided tour of the grounds and the rooms that have been preserved, which include everything from the servants quarters and the king's bedroom.
Note:There are constant efforts underway to preserve the limestone exterior of the castle, which is due to be renovated in sections in the coming years.