This is the Neuschwanstein Castle, located in Bavaria, Germany. This castle has the perfect picturesque setting amidst mountains and lakes. The construction of the castle began in 1869 but was still not completed by the time of King Ludwig II's death in 1886. Almost 60% of the rooms are unfinished, but the 40% that are completed look absolutely beautiful. I would love to see in person one day, especially in the winter as the snow makes it look even more charming.
Fun fact, it was the inspiration for Sleeping Beauty's Castle in Disneyland.