I couldn’t help shivering as I watched Wout Van Aert and Laurens Sweek duel in the Koksijde dunes this weekend during the Belgian National Championship race. It wasn’t because Sweek’s supreme sand riding skills came oh so close to pulling off a stunning upset of the World Champion. It wasn’t even because it was degrees and nuking wind outside my Belgian apartment. No, just watching that race play out along those famed Flemish dunes brought back memories from my own trip to Belgian coastal town of Koksijde for the World Cup earlier in October. The course has cemented itself into cyclocross lore, and the track is etched into my mind as the quintessential example of the Belgian Law of Compounding Suffering.

By Andrew Juiliano/Images: Balint Hamvas

The Koksijde track, like just about every other Belgian cyclocross circuit, demands a delicate balance of finesse and fitness. Power alone won’t push through these unforgiving dunes. With six major sand sections per lap, there’s no time for recovery. No room to rectify even the smallest of mistakes. Every slip up robs a little bit of energy. As the fatigue sets in, the focus deteriorates as well. Lines become harder to ride. You pedal harder to make up time. Every extra effort drains more focus. Finesse suffers. Fitness tries to make it up. Focus fleets with each compensatory effort. On and on it goes until you flail along in survival mode, praying for the lap counter to tick faster as each pedal stroke becomes increasingly labored. The suffering only compounds as the race wears on.

The paved start/finish stretch is the sole smooth portion o Koksijde. Smooth doesn’t mean easy, as a stout headwind whips off the English Channel and blows down the straight. A couple of bumpy grass chicanes later sits the Steile Helling. It has the ring of some underworld beast, though the literal translation is simply steep slope. The pain and suffering begins on this loose sand behemoth. At the crest of the loose run up there’s about 2 meters of respite. It’s not a break though, that’s the place to remount perfectly before plunging into the ruts that sweep to the right.

A brief drop through the woods begins the false flat climb to the first passage of the Zandstrook, a 200-meter off-camber dune traverse. The rut undulates along the uphill fencing, with fans screaming and flailing inches from your handlebars. They could reach out and grab you, and they occasionally do. But here you aren’t focused on the wild gesticulations. You’re focused on balancing in that narrow rut, and maintaining speed through the dune. About three meters of grass, mid-Strook, allows for a couple powerful pedal strokes and recalibration of balance before delicately powering over the final two humps and swooping right hand exit

One lapse in concentration on theses iconic sections and you’ll plow to a stop. You’ll dig deep to reaccelerate. You’ll burn those precious matches that the big dunes demand. You can push and mash on the pedals with all your might. It won’t make a difference. Lose that precious rut on the climb up the Albert Dune, the last of the major obstacles on the lap, and you’re suddenly running where you could have been gliding. The heart rate goes up. The legs get tired. You remount at the crest where the grass pokes through the dune, only to slip off line while clipping back in. It’s a waste of precious effort, only to lose time and slip further back. You push harder to stay on the bike as the rut hugs the barriers along the top of the sandy ridge. Never have you worked so hard just to go so slow.

The only way to recover here is to remain smooth. Preserve that focus as long as possible, just to save that little extra bit of fitness and finesse for later in the race. That too will eventually burn up. It always does. Float through the small ruts in between the big dunes. Nail those sandy descents off the unnamed knolls to carry speed onto the flats. The moment a bobbled line forces you to reaccelerate, the downward spiral begins. Make a mistake in the first minute, and you’ll pay for it during the next 59. There’s nowhere to hide in the storied cyclocross sandbox.

After that final squirrely descent of the Albert Dune, there’s a momentary reprieve, at least from the sand. A field of chunky grass bounces toward the starting straight, before a right spits back onto the pavement. The stiff ocean breeze blasts away any joy the smooth pavement might otherwise offer. It’s a slog into that headwind for another lap that will inevitably be harder then the previous one. While each Belgian cyclocross has its own special brand of misery–be it mud, run ups, off cambers or sand–none magnify it like those million grains of misery blowing around the dunes of the Flemish seaside.