Here we are at last, in the final stages of the Giro d’Italia. For those who remain, this might be the toughest test yet. These last climbing stages will be draining even to watch.

Thursday’s Stage 18 required riders to cover 161 kilometers (100 miles) from Oderzo to Val di Zoldo, with a 3,700 meters (12,140 feet) of climbing over a series of tough ups. A quarter of the way into the course, riders hit Passo della Crosetta, a massive climb at an average grade of 7 percent.

Friendly reminder, in cycling terms, “grade” or “gradient” refer to the steepness of a section of road. A nearly accurate way of figuring grade on roads is rise divided by run, or distance traveled vertically divided by distance traveled horizontally. The Climbing Cyclist tells us that if we’ve got a 5K-long climb in which we climb 350 vertical meters, the average gradient is 7 percent.

106th giro d'italia 2023 stage 18
Tim de Waele//Getty Images

Stage 18 also took riders into the Boite valley to climb the Forcella Cibiana (9.6K, 8 percent gradient). They then entered the Val di Zoldo for the closing ascent. Even though the final climbs are shorter, they packed a punch. The final 15K in the Val di Zoldo included two climbs, Coi, with a gradient of nearly 20 percent and the final 3K with eight switchbacks and an average grade of 6 percent. Filippo Zana (Jayco-Alula) captured the stage win while Geraint Thomas (INEOS Grenadiers) maintained his hold on the maglia rosa.

TGIF?

Friday brings us to stage 19, and it’s a doozy. The elevation profile would make a thrilling roller coaster. The day consists of 183K (113 miles) and a whopping 5,400 meters (17,716 feet) of climbing. This stage hits riders with 5 consecutive climbs, with very little time to coast.

giro d'italia, stage 19
Giro d’Italia

Riders will travel up the Val Cordevole (through Belluno, Agordo and Alleghe), then up the Campolongo, Valparola, Giau and Tre Croci passes, before taking on the closing climb to Rifugio Auronzo. The course description says the roads are in excellent condition and quite wide, with several well‑lit tunnels. The climbs also feature hairpin turns, with fast, technical descents.

But the climbing doesn’t stop until the finish line. The final ascent has a maximum 18 percent gradient, with an average of around 12 percent in the last 4K. The final, final stretch is 400 meters with a 12.5 percent grade. And then they collapse.

No rest for the weary/favorites

And finally, an incredibly difficult uphill individual time trial on Saturday before finishing in Rome on Sunday. The TT is 18.6K. (11.5 miles) with 1,050 meters (3,444 feet) of climbing. If that sounds too easy, know that the first 10K. are fairly flat. So most of the climbing is actually over the course of about 8K. In fact, there will be a zone for an optional bike swap at 9.4K in.

giro d'italia, stage 20
Giro d’Italia

The closing climb makes several hairpin turns through the woods, on narrow paved concrete. The course description says the first 5K. average 15 percent grade, peaking above 20 percent. Past the woods, the gradient falls to 4 percent for a short stretch. Then the final kilometers go up to a 22 percent grade, and then the final 150 meters to the end at 16 percent grade. Talk about earning your dessert.

Good luck, climbers. We’ll be rooting for your glutes, your quads, and your calves.