It's like the Tour de France for clowns. But falling would be no laughing matter.
The stars are Lutz Eichholz, a self-described professional unicyclist, and Stephanie Dietz, who has sixteen years of unicycling experience under her belt. And they're about to unicycle down what appears to be a straight-up hiking trail in the Dolomite Mountains.
Interestingly, unlike mountain biking, which forces riders to sit at the angle of the slope, unicylists seem able to remain mostly upright.