BBC Radio 5 Live

There's plenty of reaction and chat to yesterday's stage, plus analysis of today's stage, with OJ Borg, Rob Hayles and Rob Hatch over on the BeSpoke podcast.

You can also hear the explanation for that collapsing table.

Follow this link to have a listen, I wholeheartedly recommendend it.

One category four climb to tell you about already today. 

Jasper Stuyven was first to the top of Cote de Saint Leonard de Noblat and picked up one point.

That puts him on four points overall, and top of the king of the mountain rankings.

I realised I was mixing up my macarons and my macaroons yesterday. I'm surprised none of you pulled me up on it - if there's anything cyclists know a lot about, it's cake.

I'm more of a macaroon man myself.

(Thanks to lovelylittledetails.com for the info-graphic)

Image source, LovelyLittleDetails.com

What do you do when your desk collapses while you're commentating on the sprint finish of stage four?

You keep on going, of course.

(And save the macarons).

Timothy Foster: Finally to the Mountains! Looking forward to Froome making his first push for the Yellow Jersey 

Syrcas: That's a strong breakaway! I think it will last, Majka for the win! 

That gap to the breakaway had been steadily increasing, but it's just stabilised at 6mins 20secs. The peloton have stuck some gaffer tape over the time leak, as it were.

Image source, Getty Images/AP

With the hills upon us today, it seems fitting we start talking about the fight for the yellow jersey.

Chris Froome will be most people's pick to successfully defend his title.

But who will be his biggest concern?

Nairo Quintana? Alberto Contador? Thibaut Pinot? Romain Bardet? Fabio Aru?

Someone left-field like Alejandro Valverde?

Tell us who you think is Froome's biggest threat on this year's Tour - and explain why.

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We have a nine-man breakaway up the road. 

It consists of Greg van Avermaet, Serge Pauwels, Romain Sicard, Cyril Gautier, Andriy Grivko, Bartosz Huzarski, Florian Vachon, Thomas de Gendt and Rafal Majka.

Tinkoff's Majka will be a name that stands out there - he was king of the mountains in 2014 and has three career stage wins.

The breakaway is 6mins 15secs in front and growing - there's a genuine chance our winner today is in that group.

And so on to stage five. 

We're already under way, and while the first four days have been all about the sprinters, today we find out what our climbers are made of.

Image source, Le Tour

Image source, .

It was close. So close, you couldn't separate them with a stick insect.

Closer than an embrace between Tom Hiddlestone and Taylor Swift (Google it).

But Marcel Kittel was the stage-four winner with this ridiculously marginal victory over Bryan Coquard at the line in Liomges.

Not a huge amount happened before that, but it was worth the wait.