Those visiting Dorotheenstraße will inevitably come across the Baroque-style Landgrave's Castle with its botanically ornate castle gardens. Until 1866, the castle served as the residence of the Landgraves of Hessen-Homburg. It was built around 1679-86 by the master builder, Paul Andrich. Today, the old keep, known for obvious reasons as the "White Tower", is the only thing left of the former mediaeval castle. The chambers of the royal wing were furnished according to the taste of Kaiser Wilhelm II and his wife, Auguste Victoria. They are the only surviving testimony in Germany to the living culture of the German imperial family. The so-called "English Wing", which was newly furnished for Landgravine Elisabeth (1770-1840), is worth special mention. The rooms are designed in the old imperial manner, while the dining room features the colourful Pompeian style. The landgrave's castle is also well known for its beautiful gardens. Its fruit orchard existed as early as the 17th century. With the construction of the new castle, a formal and axial Baroque-style garden and an orangery were added to the grounds. Here, visitors will find the Lebanon cedars planted in 1820, the rose terrace and the imperial carpet beds. The castle gardens are open all year round.