LE TOUQUET, France (AFP) - Tour de France contender Alejandro Valverde said there were no easy stages on the world's greatest bicycle race as it headed back to its true homeland on Tuesday.

Following three exciting stages in England, capped by unbridled enthusiasm from millions of fans lining the roads, the Tour will grace French soil in the fourth stage from Le Touquet to Lille.

The 163.5km run has a few bumps with two fourth category climbs but is expected to end in a bunch sprint. If the English stages have taught the peloton one thing, it's that no stages on the Grand Boucle are ever easy.

"On a day when it seems like there won't be many problems, things become complicated when it starts to rain at the end of the stage," said Valverde, this year's Amstel Gold Race winner.

"That's what makes the Tour special, you don't get transition or tranquil stages.

"What's good is that I feel good and I haven't had any worries."

After three days of stress trying to avoid overzealous British fans straying into the roads, the peloton will now try to concentrate on Tuesday's stage, which risks being complicated by strong crosswinds in the north of France.

They also must try shut out thought's of Wednesday's cobbled stage five, a tribute to the epic Paris-Roubaix Spring Classic.

Twice former Tour winner Alberto Contador said he was relieved to get through England unscathed but already his mind is on the cobbles. "We survived the three days in England without issues and with the least waste of energy," he said.

"Now we have to relax before a nervous stage, and then it's the cobbles!"

When they do reach the cobbles the risk of losing time will be huge, something Chris Froome has best understood of the favourites, according to one ex-rider.

"There's one who's clearly understood and put the pressure on his rivals and that's Froome," said twice former Paris-Roubaix winner Gilbert Duclos-Lassalle.

"When you saw him contesting the sprint the first day with all the risks that entails... He showed Alberto Contador, Alejandro Valverde and all his direct rivals that he knew how to fight for position (in a bunch)."

That's a skill that will be vital on the run-in to cobbled sections.

But before they get to that fifth stage from Ypres in Belgium to Arenberg, the favourites must get through Tuesday's stage.

Yellow jersey wearer Vincenzo Nibali says stage four should not be underestimated, despite the excitement about the cobblestones to come.

"We'll have the chance to think about it when we get there," the Italian said of the cobbled stage.

"(Tuesday) will be another nervous stage. Let's get past (that), another day without any great problems, and then when we get to the cobbles stage we've got the material we need."

The big question on Tuesday will be can anyone stop Marcel Kittel.

The muscular German has won two of the opening three stages and has been imperious in the sprint finishes. Having won four stages in last year's Tour, he has already claimed half as many again this time around.

In Monday's third stage from Cambridge to London he was given the perfect lead-out by his Giant-Shimano team and was never challenged by any of his sprint rivals.

The 26-year-old was not making any predictions about how many stages he could win but he does have his eye on Tuesday's.

"So far I've won two, from now on I'll take it day by day, there are still other chances coming for us, I hope it works well. We will see," he said.

For sprint rival Bryan Coquard, who was fourth on stages one and three and has been picking up useful points in the green jersey race at intermediate sprints, as imposing as Kittel is it is his team that makes the biggest difference.

"The most impressive thing is his team - they put him in place to the millimetre, he doesn't make any effort."