Four-time Tour de France champion Chris Froome plans to ride the cobbled section of next year’s route to help prepare for the race.
The 2018 Tour, which runs from 7-29 July, features 22km of cobbled road on stage nine from Arras to Roubaix.
“Those first nine days could be extremely crucial,” said the 32-year-old Briton, who rides for Team Sky.
“It’s not a part where you could win the race but it certainly is a part where you could lose it.”
Froome has won the Tour in four of the past five years, withdrawing in 2014 after crashing twice on stage five.
The race, which will start in the Vendee region of France, also contains a team time trial in Cholet on stage three and two ascents of the Mur de Bretagne on stage six.
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Froome this year became only the third person to win the Tour and the Vuelta a Espana in the same season.
He told BBC Radio 5 live that the Tour route “is getting more and more challenging and every year”.
“I might try to have a look at some of those cobbled sections myself and go and ride them,” he said.
“I don’t have any plans to ride Paris-Roubaix or any of the one-day spring Classics, but I understand the Tour de France will incorporate some of those cobble sections from Paris-Roubaix, so I must get up there and test them out and make decision on wheels and tyres and other technical things.
“Each Tour de France I’ve won now has been a completely different challenge and that’s one of the things that makes the Tour special. We have a bit of everything.”
Froome is aiming to become the fifth rider to win the Tour five times, after Jacques Anquetil, Eddy Merckx, Benard Hinault and Miguel Indurain.
The 2018 route is the shortest this century at 3,329km.