The Hermann monument
Actually, it's best to read the website. The history of this monstrously large monument can be found at %lhttp://www.hermannsdenkmal.de/125Jahre.html%l
It seems that this exasparating warrior fought the Romans in 9 AC, luring them into the Teutoburger Forest swamps and breaking up their usually inconquerable formation, thus being able to slaughter them.
He's the hero of the region.