The Prussian Palaces and Gardens are widely acknowledged as outstanding testimonies to the history of art, culture, and architecture. But they are also the sites of historical events with an impact at both the national and the international level. To date, it has not been possible to address each and every one of these events in our permanent exhibitions. That is why, at some of these ‘historic places’, you will find a Ghost Chair with a short description along with background information available via a code.