Thursday, 11 July—Stage 18 of the Tour de France takes place between Gap and Barcelonnette. The riders are bombarded with a series of moderate climbs, and they must conquer an elevation gain of approximately 3,100 metres over a 179.5-kilometre route.

A start at breakneck speeds is expected as the first 17 kilometres run false flat downhill. The riders then enter the first and longest climb of the day, Col du Festre, which starts at moderate gradients and gradually gets steeper. The Festre totals 13.8 kilometres, and the average gradient is 4.3%. A long downhill then leads to the foot of the Côte de Corps (3.3 kilometres at 4.5%), and on it goes to the Côte de Costes (2.6 kilometres at 6%).

The riders are 75 kilometres into the race after the Costes. In fact, from the Festre onwards, they are on the Parcours of 2020’s 4th stage, which went skiing station Orcières-Merlette and was won by Primoz Roglic in a group sprint ahead of Tadej Pogacar.

After moving through Saint-Bonnet-en-Champsaur, the route goes its own way and then enters the Col de Manse (6.3 kilometres at 3.7%). A long descent brings the riders back into the valley before they climb to Chorges and continue onto the Côte de Saint-Apollinaire (7.9 kilometres at 5.2%). Right after the descent, they cross a reservoir, Lac du Serre-Ponçon, before the Côte de Demoiselles Coiffées (6.4 kilometres at 3.8%) presents the umpteenth obstacle.

A rolling section of 5 kilometres precedes a short descent and flat section along the Ubaye. After crossing the river, the route climbs for 2.7 kilometres at 4.5% before the rest of the route follows the river further upstream at very shallow gradients. This final section is almost 25 kilometres long—most of it is false flat, although the last 5 kilometres are effectively flat.

Barcelonnette had never hosted a Tour de France stage finish before.

Climbing Defined by the Number

You’re either going up, down or flat when you’re riding.

For every 100 feet, you go forward, you will also travel vertically for a certain number of feet.

You’ve got your grade if you put a percentage sign after that vertical distance.

For example, suppose you go up two feet as you go forward 100 feet. That’s a 2% grade. Suppose you climb eight feet as you go forward 100 feet. That’s an 8% gradient.

If you want to determine the status of climbs by the numbers, we can look at the classification system used in most professional races.  That would mean climbs are classified as 4, 3, 2, 1 (and Hors Categorie or “HC” in the Tour de France.)  This determination is made by a combination of length in kilometres and average gradient, with the position of the climb in the route and the degree of road surface being lesser determinants.  See below:

  • Category 4 – the lowest category, climbs of 200-500 feet (70-150m). Length is usually less than 2 miles (3km)
  • Category 3 – climbs of 500-1600 feet (150-500m), between 2 and 3 miles (3km and 4.5km) in length.
  • Category 2 – climbs of 1600-2700 feet (500-800m), between 3 and 6 miles (4.5km and 10km) in length.
  • Category 1 – climbs of 2700-5000 feet (800-1500m), between 6 and 12 miles (10km and 20km) in length.
  • Hors Category (HC) – the hardest climbs of 5000+ feet (1500m+). Usually more than 12 miles (20km) in length

As for gradients, typically, the average gradient has to be above 4% to classify a climb.  Hors Category (HC) generally climbs on average of>10% or has an extreme length at a slightly lesser grade.

Related articles