Welcome to the Walpurgishalle, 1901
Here is something special for Walpurgisnacht. As I wrote here (five years ago!):
Walpurgisnacht is celebrated in Germany on 30 April (Beltane or May Eve). On this night witches are thought to fly to a plateau on Brocken Mountain deep in the Harz Mountains … The plateau is known as the Hexentanzplatz, the witches’ dancing place … it is here that Goethe set the witches’ sabbat in his Faust (1808, 1832). By the turn of the century a thriving tourist industry had prompted the publication of numerous witch-themed postcards.
You will find these postcards here, here, here and here. Later in 2006 I explained that, “By the 1920s, another tourist gimick was added: Brocken ‘money’ (Brocken or Thale Notgeld).” You will find images of Brocken money here and here.
And now I can add the Walpurgis Hall (Walpurgishalle), which was built at the Hexentanzplatz by the Berlin architect Bernhard Sehring in old-Germanic style in 1901. Carved across the front of the building above the doorway to the Walpurgishalle is a frieze. The head of Wodan crowns the pediment, flanked by the Ravens Hudin and Munin (which symbolize his thoughts and memories) and the wolves and Gari Freki, who are his guards and agents.
Today the Walpurgishalle is a museum. Hermann Hendrich (1854–1931) created five large paintings for the interior of the hall showing scenes from the Goethe’s Faust. These are
 Irrlichtertanz (Erring light dance) [postcard no. 3]
 Mammonshöhle (Mammon’s Cavern) [postcard no. 5]
 Hexentanz (witch dance) [postcard no. 6]
 Windsbraut (wind bride) [postcard no. 4]
 Gretchenerscheinung or Gretchentragödie (Tragedy of Gretchen) [postcard no. 3]
Reproductions of these paintings were published in a book (which I don’t have) and a series of postcards (which were hugely popular, and which I do have). Three more images appear in the postcard series:
 “Hexenfahrt” (witch journey) [postcard no. 1]
 Walpurgishalle—Hexentanzplatz [postcard no. 7]
 “Sternenreigen” (star dance [lit. roundelay]) [postcard no. 8]
For an insight into the paintings, which can be seen much more clearly in the photos by Raymond Faure. You will find a page of his excellent photos of the Walpurgishalle here. This panorama below might help orient you.