Britain's Geraint Thomas wins stage one
Welshman clocks 16 minutes four seconds for 14km time trial
Team Sky team-mate Vasil Kiryienka is second
Defending champion Chris Froome sixth
GC contender Alejandro Valverde out after big crash
Chapeau, Geraint Thomas. The TV director has had a nightmare, though.
Not a single picture of Thomas flying round the course until the British Team Sky rider zooms across the line to post a stonking time of 16 minutes four seconds
That's seven seconds quicker than team-mate Vasil Kiryienka, who Thomas knocks into second place.
What a ride. Well it must've been, we just didn't get to see any of it.
Romain Bardet comes home in a respectable 16 minutes 55 seconds - on a par with Jakob Fuglsang.
Hang on, who is this steaming up behind him?
Rob Hayles
Former GB cyclist on Radio 5 live sports extra
Romain Bardet has the expectations of France on his shoulders. Many of his countrymen have crumbled under that pressure from the media and the public but he hasn’t shown signs of that yet. We will find out by stage five what sort of form he is in.
Romain Bardet is approaching the final stages of his ride...he's already slower than Kiryienka but can he limit his losses?
Big spill for Lotto Soudal's Tony Gallopin, who clatters into the barriers after over-cooking a corner.
A reminder of the dangers out there for the remaining challengers.
Thankfully, he's up and riding again.
Astana's Jakob Fuglsang, an outside contender for the overall, comes home in a time close to 17 minutes and that's a big boost for Simon Yates, who was around 16 seconds quicker.
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Britain's Simon Yates stops the clock 30 seconds down on leader Vasil Kiryienka.
That's a good effort from the Orica Scott rider, who is not renowned for his time trialling.
It all depends what his general classifcation rivals do, though.
The big names are coming up...
Philippe Gilbert, who won the Tour of Flanders and Amstel Gold Race this year, continues his fine form to come home in 10th for the time being.
Alberto Contador has won all three Grand Tours at least twice, but while the 34-year-old Spaniard is not as feared as he once was, he will be a marked rider.
Expect dancing on the pedals and sharp attacks in the high mountains as the Trek-Segafredo rider tries to shake up those chasing podium places.
Contador goes off at 17:29 BST. We've just had a glimpse of him warming up.
Image source, Getty ImagesRob Hayles
Former GB cyclist on Radio 5 live sports extra
British rider Simon Yates is coming in under the radar, he will be looking for a stage win and to encroach on the general classification like his twin brother, Adam. They are both as talented as each other.
It was a good move by them to go to an Australian team as they are looked after so well by the team directors there. It wasn't a bad decision to not join Team Sky.
Simon Yates has just reached the checkpoint at nine minutes 40 seconds.
What price a French winner? Home fans will not need reminding they have had little to celebrate since Bernard Hinault's victory back in 1985.
Romain Bardet carries the weight of the nation's expectations this year. The 26-year-old AG2R-La Mondiale rider finished runner-up to Froome in 2016, but he was more than four minutes adrift. Again, a lack of individual time trials will help the climbing specialist, but can he take on Froome in the high mountains?
The great French hope has just got his time trial under way...
Image source, Getty ImagesShould riding the Giro catch up with Nairo Quintana, his team Movistar also have Spanish veteran Alejandro Valverde in their ranks.
The 37-year-old won his home tour - the Vuelta a Espana - in 2009 and has had seven other podium finishes, including third at the 2015 Tour.
A controversial figure, who served a two-year doping ban, the wily, versatile Valverde seems to almost be getting better with age. A first tour title at 37 is surely beyond him though. Right?
He starts at 17:08 BST.
Image source, Getty ImagesRob Hayles
Former GB cyclist on Radio 5 live sports extra
Mark Cavendish has been really held back by his time off with glandular fever after his four stage wins last year, it is hard to predict what can he do this year.
Ah, Castroviejo has faded from contention in the second half, coming in a provisional seventh place and 13 seconds behind Vasil Kiryienka, whose time of 16 minutes 11 seconds is looking better and better.
Mark Cavendish is away. He'll just be looking to get round safely today, with tomorrow's stage to Liege set to end in a sprint finish.
The British sprinter is hoping to equal, or even surpass, Belgian legend Eddy Merckx's record of 34 Tour stage wins this year
The 'Manx Missile' starts his 11th Tour on 30 and in half of the previous 10 he has won at least four stages.
And with nine designated 'flat' stages this year, you would think there would be ample opportunity for the Dimension Data sprint specialist to add to his tally.
Image source, Getty ImagesHowever, the 32-year-old has missed three months of this year after being diagnosed with glandular fever, caused by the Epstein-Barr virus.
Cavendish returned in the Tour of Slovenia in mid-June and also rode in the British national championships, on the Isle of Man.
He seems to fare best when written off though - Cavendish went into last year's race unsure of his form after spending much of the year training for an Olympic medal tilt on the track in Rio and he went on to claim his first yellow jersey and four stage wins.
Rob Hayles
Former GB cyclist on Radio 5 live sports extra
We need to remember there are two races in one here, the individual stage winner and the time difference between the racers fighting for the overall winner.
Spain's Jonathan Castroviejo is out on course and going well - the Movistar rider could well threaten the top positions with a strong second half.
Meanwhile, Adam Hansen of Lotto Soudal has just crossed the line. His time of 18 minutes three seconds is nothing spectacular.
However, what is notable is that the Australian is competing in his 18th consecutive three-week Grand Tour and the 25th of his career.
Madness. Brilliant but utter madness.
BBC Radio 5 live sports extra
Here are Simon Brotherton and Rob Hayles keeping a watchful eye on proceedings from their commentary box near the finish line.
You can listen to them via the link at the top of this page...
Image source, BBC SportNairo Quintana is one of the few who can ride away from Chris Froome in the mountains and the paucity of time trialling this year will also help the 27-year-old Colombian's cause - but he needs to be more aggressive.
It will be interesting to see if the Movistar rider, who has twice finished runner-up to Froome (2013 and 2015) is helped or hindered by competing in Italy's equivalent race, the Giro d'Italia, where he finished second in May.
He led the Giro going into the last day but, as expected, lost out to Tom Dumoulin on the final-stage time trial. Will that disappointment fire him up to attack in this Tour?
Image source, Getty Images