Following that, a UKC user Holger dropped us a line to show us this interesting video (in German) about Thomas Willenberg and Wulf Schneider buildering in Berlin, Germany.
There is a strong history of urban climbing in Berlin. For more information check out this previous UKC Article about climbing on the Berlin Bunker.
Holger told us about the following video:
"At 2:42 min you will find a boulder called "FEINDESLIEBE" (EnemyLove) Font 8B+/8C, and in my opinion the hardest builder in the world."
Is this the hardest builder in the world? We have no idea. Do you?