From the Colonel's Regiment
The Intermediate Fass is situated in 6 Heidelberg castle. It is situated in the ante-room just outside the room housing the Grosses Fass. It has clearly been placed there to dupe tourists, who enter the room and are so amazed by its size that they immediately pause to take photographs of themselves standing in front of it. As the continue their walk into the room, they realise their mistake as they encounter the actual Grosses Fass. I am sorry to report that the Colonel's Regiment did fall for this scam during Mission 6 6 Heidelberg.