What is it?
It's the 2022 London Marathon. Last year was the first time the event has take place on its traditional course in October, rather than the spring.
When is it?
The marathon takes place on Sunday, October 2.
What time does it start?
08.30: Mini London marathon
08.50: Elite wheelchair races
09.00: Elite women's race
09.30: Elite men's race and mass start
What TV channel is it on?
The elite races and the mass participation event on Sunday will be broadcast live on the BBC from 08:30 BST - across BBC One and BBC Two, as well as the Red Button and iPlayer.
You can, of course, also follow full live coverage with us through our live blog.
What are the current marathon records?
2hrs 1mins 09secs is the men's fastest time, set by Kenyan Eliud Kipchoge in Berlin in 2022.
The average time for male runners is around 3 hours 48 mins.
Brigid Kosgei set the women's world record of 2:14:04 at the 2019 Chicago Marathon.
4 hours 23 mins is the average time for female finishers.
Mo Farah has pulled out of Sunday's London Marathon due to a hip injury.
The four-time Olympic gold medallist, 39, suffered a problem to his right hip in training and will not be fit.
He said: "I've been training really hard over the past few months and I'd got myself back into good shape and was feeling pretty optimistic about being able to put in a good performance at the TCS London Marathon.
"However, over the past 10 days I've been feeling pain and tightness in my right hip. I've had extensive physio and treatment and done everything I can to be on the start line but it hasn't improved enough to compete on Sunday."
Farah, who was set to compete in his first marathon since 2019, was looking in good shape, having won warm-up race The Big Half earlier this month.
However, he intends to race in 2023 when it switches back to its traditional date in April.
Farah added: "It's really disappointing to have to withdraw after a good last few months and after my win at The Big Half but also because I love racing in front of my home crowd in London who always give all of us athletes such amazing support.
"I wish everyone taking part on Sunday a good run and I hope to be back out there with you in April 2023."
What is the latest weather forecast?
At the moment the forecast is for sunshine, with temperatures hovering in the mid teens, with a high of 18C.
How will transport be affected?
Roads will be closed across south east and central London between 4am and 7pm, while buses in central London and Greenwich will terminate early, or be diverted, from 6.30am to 7.30pm. DLR will run a changed service until 5pm.
Runners in Sunday’s marathon will face disruption to their preparations due to the national train strike on Saturday, which is forcing some participants either to travel on Friday or drive.
Positive talks have been held with Southeastern Railway and National Rail with regard to Sunday when the tube and Docklands Light Railway are operational.
Plans are also in place to counter any disruption from protests. The group Just Stop Oil are planning a two-day protest in the capital this weekend and London Mayor Sadiq Khan has already urged them to steer clear of the 40,000 runners who will raise around £70 million for charities which include those dedicated to climate change.
“What the London Marathon is about is inspiring people to use their legs, to exercise - not use transport - and is about charity fundraising,” said Brasher. “We have appropriate measures in place but we really hope the race won’t be disrupted.”
What is the route?
The course is very flat with only one small rise. The triple start winds out of Greenwich Park and Blackheath Park, loops through Greenwich and across Tower Bridge. Circling Canary Wharf the course runs along the Thames past the Tower of London through Trafalgar Square and onto The Mall where you will finish in front of Buckingham Palace. The course is one of the worlds fastest and boasts of the existing women's world record.
What are the best viewing spots?
Here's what the official London Marathon website suggests...
If you want to follow your loved ones and try to get a glimpse of them as they pass, we suggest that you avoid very crowded areas, where it can be difficult to find a viewing spot, hard to move around and tough to get in and out.
Busy areas include Greenwich town centre and the Cutty Sark. While the ship is undoubtedly a beautiful backdrop for the race, the crowds that are attracted here can make spectating uncomfortable and transport in and around Greenwich becomes particularly busy. We strongly advise spectators to avoid this area.
Tower Bridge is always extremely busy, as is anywhere from mile 24 to the finish in The Mall. Obviously many of you will eventually end up in this area later on in the day as you head to the runner meet and greet area in Horse Guards Road.