The gap to the 30 men at the front of the race is hovering around 4mins 30secs.

Now, I was talking about Chris Froome and Team Sky being happy to let that group march off into the distance, but they can't let it slip too much.

Sebastien Reichenbach is among the race leaders and he's actually just 11mns 41secs behind Froome in the general classification.

The Swiss is not a yellow jersey threat, but Sky will have no interest in relinquishing the maillot jaune, even for a day.

Image source, EPA

Today's stage will be a series of postcard moments. Cute villages, stunning peaks and a shimmering lake.

What are cycling's most beautiful views?

You tell us. And if you've taken a photo - show us.

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Rob Hayles
Former GB cyclist

Stage 15 features 160km with six climbs - I think there's probably about a yard of flat per climb on this stage. 

If anybody is struggling, it's going to be an awful day for them.

A war of attrition awaits. 

Image source, Getty Images

After moving north yesterday, we are now very much in the east of France, edging closer to the Swiss border.

The route traverses the Ain region - which of course hosts the mountainous Tour de l'Ain and features Grand Colombier.

These are the Jura Mountains, setting us up nicely for when we get into the Alps, but look out for the beautiful Lake Bourget, which is shadowed by the hulking Colombier.

The descent of Col du Berthiand, and the slowing peloton, has enabled plenty of those dropped riders to get back into the group.

Chris Froome has a full quota of Team Sky team-mates around him - meaning his rivals will look around and see plenty of black and blue jerseys.

The gap between the peloton and leaders is 4mins 7secs.

Reaction, analysis, thoughts, opinions - it's all in last night's BeSpoke podcast.

I would suggest having a listen while watching the early part of today's stage.

You can listen here.

Geraint Thomas
Team Sky Tour de France rider

Image source, Getty Images

Here's what Team Sky's Geraint Thomas said about today's stage in his Tour de France preview, which you can read here.

"This will be one of the hardest days and not just because of the amount of climbing involved. The yellow jersey will be on the back of one of the favourites by now so nobody will be bothered about chasing those in the break.

"However, the make-up of the break is important - it could be smaller teams wanting a rider in there for added exposure, or riders chasing King of the Mountains points - so it could be hectic for the first hour until the right selection of riders are allowed to go clear."

Worth repeating though that there are no general classification contenders at the front of the race.

Chris Froome, in the yellow jersey, is very happy in a slowing peloton - 2mins 46secs behind - alongside rivals Adam Yates, Bauke Mollema and Nairo Quintana.

Quintana's Movistar team-mates in the front group will only prove useful if the peloton gets close later on - they could potentially help him out down the road.

Rafal Majka and Ilnur Zakarin are caught by the group of 28 chasing from behind.

Some of the names in there are Vincenzo Nibali, Thomas Voeckler, Serge Pauwels and Tom Dumoulin.

Two Movistar riders in there - none from Team Sky.

Rob Hatch
BBC Radio 5 live commentator

The top ten riders in the general classification are separated by five minutes and 16 seconds, but a lot of things can change...and that's because stage 15 is pretty horrible to look at.

It's hard, it's high and if you lose control early on, that's when the panic starts to set in.

It could be chaos out there.

Image source, Le Tour

If this stage were a Mr Men character, it would be Mr Bump.

Six classified climbs - the most of any stage this year - including two first category climbs and an hors category.

We've just ticked off a category one climb.

There are plenty of opportunities to rattle the peloton with attacks and there is likely to be a break.

Breaks won't concern Chris Froome, assuming they don't contain any of his rivals.

But the pair of ascents on Grand Colombier towards the finish could cause all kinds of mayhem.

Right. That's the first climb out of the way and we can take stock.

Chris Froome is safely in the peloton with his yellow jersey rivals - none of the men up the road are a concern to him.

Vincenzo Nibali is leading a group to chase down the leaders.

He shows a wonderful turn of speed just before the summit of this category one climb up Col du Berthiand.

Ilnur Zakarin is not a king of the mountains threat, and it looks like Rafal Majka just had a little chat with the Russian to make sure he wasn't going to nick maximum points.

It's a sound agreement - Majka is allowed to collect 10 points.

Rafal Majka, alongside Ilnur Zakarin, is 20 seconds up the road and he has king of the mountains points on his mind.

He's 13 points behind polka dot wearer Thomas de Gendt. Daniel Navarro, third on the list, is looking to join Majka at the front of the race.

All those attacks and bursts right from the start have picked off a few from the herd.

Plenty of sprinters are off the back of the peloton - including Mark Cavendish, Dan McLay, Andree Greipel, Marcel Kittel and John Degonkolb.

Team Sky's Luke Rowe has struggled to keep up too.

And Vuillermoz drops out at the front, but is replaced by Zakarin, who joins Majka in the lead.

And here's another push - Rafal Majka and Alexis Vuillermoz have put some daylight between themselves and the peloton.

Ilnur Zakarin is trying to bridge the gap.

It's been a later start than usual today - we're only 30 minutes into the stage.

But the first climb is upon us - a category one ascent - and there's been plenty of attacks off the front of the peloton.

Thomas de Gendt, the polka dot jersey wearer, has been monitoring affairs, but Tony Gallopin did get away briefly before being reined in.