Following the reconnaissance of the route carried out today by Thierry Gouvenou, the organisers have set a difficulty level for each of the 29 cobblestone sectors of the race. The star rating is based on their length, the irregularity of the cobblestones, the overall condition of the sectors and their position in the race.
This year, 55km of cobblestones will feature on the 2017 edition over the race distance of 257 kilometres. With the conditions set to be relatively benign, with no rain forecast and only light northerly winds predicted.
That will mean that the cobbles and length of the course will be the major factors in determining who emerges as the strongest in the Roubaix velodrome. Last year, it was Mat Hayman who took the win in unbelievable circumstances but there will be a host of riders looking to replace the veteran Aussie at the top of the podium.
The decisive cobbled section changes from season to season and often the race isn't wholly decided on the pave of northern France, with the race often still in the balance as the riders hit the famous velodrome in Roubaix.

Mathew Hayman crosses the finish line ahead of Tom Boonen and Ian Stannard (Getty) Source: Getty Images
The ratings of the cobbled sectors remain, but there has been a colour system introduced as well, to tell difficulty at a glance. Black represents the five-star sectors, with red, orange, yellow and green as the descending levels of difficulty.
The Cobbled Sectors:
97 km Troisvilles to Inchy (2.2km) / Rating : ***
103.5 km Viesly to Quiévy (1.8) / Rating : ***
106 km Quiévy to Saint Python (3,7km) / Rating : ****
112.5 km Viesly to Biastre (3km) / Rating: ***
116 km Biastre to Solesmes (0,8km) / Rating : **
124.5 km Vertain to Saint-Martin-sur-Ecaillon (2,3km) / Rating : ***
134.5 km Verchain-Maugré to Quérénaing (1.6km) / Rating : ***
137.5 km Quérénaing to Maing (2,5km) / Rating : ***
140.5 km Maing to Monchaux-sur-Ecaillon (1,6km) / Rating : *** Thierry Gouvenou says: “This could be a key sector in the race. In 2016, it was here that the first selection was made, spurred on by Tom Boonen”.
153.5 km Haveluy to Wallers (2,5km) / Rating : ****
161.5 km Trouée d’Arenberg (2,4km) / Rating : ***** Thierry Gouvenou says: “This is one of the legends of Paris-Roubaix. You can't win the Hell of the North in the ‘Trouée', but you can certainly lose it”.
168 km Wallers to Hélesmes (1,6km) / Rating : ***
174.5 km Hornaing to Wandignies (3,7km) / Rating : ****
182.5 km Warlaing to Brillion (2,4km) / Rating : ***
185.5 km Tilloy to Sars-et-Rosières (2,4km) / Rating : ****
192 km Beuvry-la-Forêt to Orchies (1,4km) / Rating : ***
197 km Orchies (1,7km) / Rating : ***
203 km Auchy-lez-Orchies to Bersée (2,7km) / Rating : ****
208.5 km Mons-en-Pévèle (3km) / Rating : ***** Thierry Gouvenou says: “This is one of the key sectors of Paris-Roubaix. The uphill portion in the second half will oblige the strong riders to show themselves. The race order at the exit of this sector often reflects that of the arrival”.
214.5 km Mérignies to Avelin (0,7km) / Rating : **
218 km Pont-Thibault to Ennevelin (1,4km) / Rating : ***
224 km Templeuve (0,5km) / Rating : **
230.5 km Cysoing to Bourghelles (1,3km) / Rating : ***
233 km Bourghelles to Wannehain (1,1km) / Rating : ***
237.5 km Camphin-en-Pévèle (1,8km) / Rating :**** Thierry Gouvenou says: “This is THE decisive sector of Paris-Roubaix. The favourites will have to give it everything they've got left”.
240 km Carrefour de l’Arbre (2,1km) / Rating : ***** Thierry Gouvenou says: “This is the moment of truth”.
242.5 km Gruson (1,1km) / Rating : *
249 km Willems to Hem (1,4km) / Rating: ***
256 km Roubaix (0,3km) / Rating : *

The 2017 route. (ASO) Source: ASO