This picture gallery is a collection of artworks and sculptures originally amassed by Frederick II…read morein the mid-18th century. As was befitting major artwork collectors of the time, the gallery included pieces by masters such as Rubens, van Dyck, Rembrandt, Raphael, Titian and Guido Reni. Displayed by painting schools, artists were divided into east and west sides of the gallery. Over time the artworks in the collection experienced major changes--in 1830 56 pieces were allocated to what became the Altes Museum, in Berlin, then additional lost or destroyed during WW II. The 62 remaining paintings were subsequently supplemented with more pieces and sculptures in the early 19th century.
Built on the site of a former greenhouse, the exterior is modest compared to the ornate gilded finishes and Carrera marble walls and floors on the interior. Paintings are arranged along one wall with windows opposite, and there is a small gallery room at one end featuring some of the smaller scale artwork.
November thru April this gallery is closed. During other months of the year, opening hours are 10-5:30pm similar to the other buildings in Sanssouci Park. Tickets for this individual building are €8 regular adult or €6 reduced (for children, seniors, disabled attendees), or can be booked as part of the Sanssouci+ package for €22 regular adult or €17 reduced. There are separate combo or family tickets available online or in-person too. Expect to spend about 20-30 minutes here though with the audio guide (free if I recall correctly) you could probably spend longer listening to more info about the various artworks.
The building is not wheelchair accessible. Also if I remember correctly bathrooms are available in the main palace building though not here.
Fun fact: in G-maps you can virtually walk thru the gallery.