The Harnack House was built in 1929 as a conference center and guest house for the Kaiser-Wilhelm-Gesellschaft.
In June 1942 an important meeting took place at the Harnack House between leading phsicists and chiefs of German war production. The Germans decided at this meeting not to assign priority to the building of an atomic bomb.
After the war, the Harnack House became an American officers club and visitors quarters.
The Fiddler Green Bar was located at the ground floor. Every friday afternoon there was “happy hour” with raffle, small prizes and karaoke. In the hallway to the bar there were glass cabinets where the beer mugs of the club members were displayed.
The Marine Bar was a nice place to enjoy the Saturday nights. At the early Sunday morning the outer appearance of the guests has changed.
Affiliated to the club there was a hotel.
The building is now used by the Max Planck Gesellschaft