Marienburg Castle, also known as Neuschwanstein of the North, is a 19th-century neo-Gothic castle located in the town of Pattensen, Lower Saxony, Germany. It was built as a summer residence for King George V of Hanover and his wife Queen Marie in 1858-1867. The castle was designed by the German architect Conrad Wilhelm Hase, and its construction was overseen by the renowned architect Edwin Oppler.

The castle features a stunning combination of Gothic Revival architecture and medieval design elements. It is surrounded by beautiful gardens and landscaped parkland. The interior of the castle is equally impressive, with elaborately decorated rooms, beautiful stained glass windows, and an extensive collection of artwork.

The castle was used as a royal residence until the end of the monarchy in 1918. After that, it served as a museum, a hospital, and even as a film set. In 2004, the castle was acquired by Prince Ernst August of Hanover, and it has been restored to its former glory. Today, visitors can take a guided tour of the castle and its beautiful gardens, and admire the breathtaking views of the surrounding countryside from its towers.