Baroness Tanni Grey-Thompson
11-time Paralympic champion on BBC One

Marcel Hug and David Weir are starting to line themselves up for the final sprint. They are all just lining themselves up because you have to be in a straight line to get as fast a time as possible.

As the mass field gets underway the mini-marathoners have all finished their runs.

Our man behind the finish line - Tom Gayle - is going to catch up with some of them and you can watch that NOW on the last stream of the carousel above.

Image source, BBC Sport

This men's wheelchair race almost looks certainly to be coming down to a sprint finish in central London. There is a group of nine at the front which includes both David Weir and Marcel Hug.

A few of the athletes sit up in their chair to take a breather as they free-wheel down on the many hills on this course.

In the women's race the leaders are currently weaving their way through the shadows of Canary Wharf. Manuela Schar and Tattyana McFadden are in the leading group.

We're about 10 minutes from the finish.

Mary Keitany is aiming to break the marathon world record set by Britain's Paula Radcliffe 15 years ago.

The Kenyan is looking good so far at the 10-mile mark, while her main rival Tirunesh Dibaba has fallen off the pace.

Image source, .

Paula Radcliffe
Women's marathon world record holder on BBC One

Both ladies are in great shape and the conditions are perfect today - it's a very fast course and I'm sure they will benefit from the crowd out there and the magic of the London marathon.

The elite women have just crossed the 15km mark and it's still the same two out in front.

Last year's winner Mary Keitany and runner-up Tirunesh Dibaba both clock 47:46 minutes and they've created a minute's gap ahead of the chasing field.

Francesca Rajan: Already in tears watching t, externalhe London Marathon coverage. I’ll be entering the ballot!

Pheobe Dawson: I always get a little emotional watching the London Marathon, more so on days like today when friends and loved ones are running. Best of luck to all runners, you epitomise the finest qualities of the human spirit.

Becky Rossington: Got all my running gear on to watch the London marathon. Hopefully will help me kick start my training.

Off we go! The Queen has sounded the klaxon from Windsor.

Don't forget you can watch the 41,469 runners live on BBC One and at the top of this page.

The elite men are lining up ready to go, and the racers in the mass start will get going in waves just behind them.

The Queen will officially get things under way from Windsor Castle.

There's only one thing left for us to say...

GOOD LUCK, EVERYONE!

Paula Radcliffe
Women's marathon world record holder on BBC One

It’s a difficult question for the men’s race and I think Eliud Kipchoge is capable of breaking that world record. But because the field is so strong here, I just don’t see him risking everything on going out for that world record, he will just concentrate on winning the race.

Steve Jones was an inspiration to me, and was light years before his time when he set the British record in 1985, but Mo Farah is absolutely capable of beating it. The way the race is planned and the way it is run in the first half is going to determine the final time.

We're through the halfway point now in the men's wheelchair race.

American Daniel Romanchuk is on the front of the leading group which includes both David Weir and former champion Marcel Hug.

A little further back on the course in the women's race, Tattyana McFadden is leading the way with defending champion Manuela Schar a few seconds back.

It's looking like a good finish in both races!

Apart from Mo Farah, here are the star racers to look out for in the elite men's race:

• Daniel Wanjiru (Kenya) - The defending champion who claimed his first major marathon title in London last year.
• Kenenisa Bekele (Ethiopia) - Bekele's 2:03:03 finish in Berlin in 2016 made him the second quickest marathon runner in history. He finished second in London last time out.
• Eliud Kipchoge (Kenya) - Having moved up to marathon level in 2013, Kipchoge won the London title in 2015 and 2016 and went on to become Olympic champion.
• Bedan Karoki (Kenya) - He clinched third place on his debut in London last year and ran the fourth fastest half marathon in history in the United Arab Emirates in February.

Image source, Getty Images

It's hot hot hot in London.

If you want to know more about running in the sun, here are a few tips from BBC News.

Image source, Getty Images

Current British marathon record holder Steve Jones believes Mo Farah "has a great chance of beating his record this afternoon".

Speaking to BBC Sport, Jones said: "Mo has got all of the tools to beat my record - he has got speed, endurance and a good experience at running at big events.The cream of the runners in the race will be nervous about Mo in the race."

Four Olympic gold medals, six World Championship golds, five more from European Championships.

But there's still one accolade that eludes Sir Mo Farah, and that's a marathon title.

In his only attempt, in London four years ago, he finished eighth in two hours eight minutes 21 seconds.

It sounds uber quick, but it was far off the British record.

The 35-year-old has now permanently left his track career behind and is concentrating on the road.

"It's really hard to get your pacing right in a marathon," said the BBC Sports Personality of the Year holder.

"You will have a couple of groups the race will break into, and in 2014, to be honest, I thought I could just work my way through from the back. And I remember thinking, 'I can't go any faster. I can only keep going'.

"The biggest lesson I learned is to stay patient, and that at some point it's going to get tough. And then to try to pick up my drinks. You have to stay hydrated, you have to save as much energy as you can."

Image source, Getty Images

It's Tirunesh Dibaba - last year's runner-up - who leads the way in the women's race after 5km.

The Ethiopian clocks 15:46 minutes - a second ahead of defending champion Mary Keitany.

Paula Radcliffe
Women's marathon world record holder on BBC One

Mary Keitany's pacemaker is indicating to her that she needs to back off and to stop going so fast in the early stages. The first mile is for free almost, and you can go a little bit faster but then settle in after that. Keitany likes to attack the race whereas Tirunesh Dibaba likes to sit back a bit more.

Image source, Reuters

Whether you're an athlete running the gruelling 26.2 miles, or a family member cheering on from home - we want to hear from you.

Get in touch on Twitter via #getinspired , externalto send us your pictures, videos and good luck messages.

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