The hardest climb in cycling?

A profile, complete with ominous photos, of The Koppenberg, a contender for the title of "toughest climb in cycling."

The Koppenberg's stats are, objectively speaking, nothing to go home crying about. I know, sacrilege, you howl. Hear me out. There are climbs that are steeper, longer, even harder. It's only 600 meters long, it averages just under 12%, and its steepest section is 22%. I'm not saying these are paltry figures, but climbs like the Zoncolan and Angliru manage figures like that for ten thousand meters. They're debilitatingly hard, but so is the Koppenberg. There are a few things that are very, very different about the Koppenberg that set it well apart from the horror climbs of the Zoncolan and the Angliru, namely: cobbles, cobbles, cobbles, and the Ronde van Vlaanderen.

I haven't done a lot of riding over cobblestones. It's not pleasant, though it gives one a sense of joining some gladiatorial fraternity. But watching professionals suffer over them is good fun.