They are just themed differently. The castle is all castle theme, the hotel has Lego Friends, Adventure, Pirate, Kingdom, and Ninjago.
The hotels have different themes. I have never stayed at either one. I have been in both lobbies, and I can tell you this. They are both adorable.
Yes they are themed differently, and the castle is newer. They have an all you can eat breakfast buffet included at castle, heated pool, jacuzzi, and shows. They have a big outdoor playground and outdoor theatre at Castle too. I highly recommend spending the extra money to go the Castle. It was the coolest hotel I've stayed at and I have stayed at many 5 star resorts all over the world.
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