As one of the most significant collections of its kind, the Old Masters Picture Gallery is highly regarded. Wilhelmshöhe Palace It enjoys worldwide reputation. It can look back on a history of over 500 years and dates back to landgrave ownership.

The exhibition offers an excellent overview of European painting from the Late Gothic period to Classicism on three floors. A particular focus is on Dutch and Flemish painting of the 17th century, with numerous masterpieces by Rubens, Frans Hals, Van Dyck, and Jordaens. The collection of Rembrandt's works, including the famous paintings "Jacob Blessing the Sons of Joseph" and the portrait of Saskia, is one of the largest in the world. The areas of Old German, Italian, French, and Spanish painting are represented by works by Dürer, Titian, Poussin, and Murillo, among others.

The origins of the Picture Gallery date back to the year 1509, when Lucas Cranach the Elder created a small altarpiece in memory of Landgrave Wilhelm II. The period of most intense collecting activity was between 1748 and 1756, when Landgrave Wilhelm VIII acquired around 800 paintings in Holland, Paris, Brussels, Antwerp, Venice, and Germany through his diplomats and art agents. Between 1749 and 1751, a separate gallery building was constructed behind the Landgrave's palace between Auehang and Frankfurter Straße for the collection. In 1877, the paintings were moved to the newly built building of the current Neue Galerie on Schöne Aussicht, where they remained until the outbreak of World War II. Since 1974, the Picture Gallery Old Masters has been located in Wilhelmshöhe Palace.

The Kassel Antiquities Collection in the ground and basement floors of Wilhelmshöhe Palace provides an overview of past cultures in the Mediterranean region. Around 800 exhibited objects range from the Bronze Age through the heyday of Greece to the Roman Empire, giving an overview of the artistic development of the various ancient civilizations. They tell of the collecting passion of the landgraves and show the reception of antiquity in Kassel. The tour leads from the "Living Antiquity" through the "Legacy of the Landgraves" to "250 Years of Antiquities Collection".

In the main hall ("Living Antiquity"), portrait heads of emperors and private individuals dominate the exhibition on the everyday culture of the ROMANS. The area ARCHAEOLOGY displays exhibits from various sites, such as those from the Kassel excavation on Samos. Many marble SCULPTURES convey to the visitor the beauty of ancient sculpture. Symposium, competition, and theater are often depicted on vases, illustrating the everyday life of the GREEKS. A theme permeating everything in antiquity is the MYTH, the diversity of which is particularly vividly preserved in vase paintings. The specially designed "Rome Hall" provides information on the history of the collection.

In the basement, the 30 large-format historical cork models are exhibited, which Landgrave Friedrich II of Hesse-Kassel acquired in Rome at the end of the 18th century. This is one of the most extensive collections of such models worldwide.