In 2027 the TCS London Marathon becomes a two-day event, on Saturday 24 and Sunday 25 April, with 100,000 runners expected, according to London Marathon Events. The organisers say it is the first and only time the race will be split across a weekend, a format they call The Double. For anyone in South Buckinghamshire who is running, supporting or simply needs to cross London that weekend, it means planning around road closures on two days instead of one.
- 2027 is The Double: races on Saturday 24 and Sunday 25 April, with women's and men's elite and good-for-age fields running on separate days.
- The course starts around Blackheath and Greenwich, crosses Tower Bridge at halfway and finishes on The Mall.
- Road closures, parking suspensions and footpath closures apply along the route, with signed vehicle crossing points at set times.
What is different about the 2027 London Marathon?
Usually the Marathon is a single Sunday in April. For 2027 it spreads across both days of the weekend so that around 100,000 people can take part. Female elite and good-for-age entrants run on one day and male elite and good-for-age entrants on the other, as reported in the event's history. Mass-participation runners are spread over the two days.
For travel, the practical point is simple. Expect the route to be closed on the Saturday and again on the Sunday, and check which day your runner has been allocated before you book anything.
Where does the Marathon route go?
The race begins at three start areas around Blackheath in Greenwich and follows a largely flat course along the Thames. It passes the Cutty Sark at about 10km, crosses Tower Bridge at halfway, loops through Canary Wharf on the Isle of Dogs, then heads west along the river past Big Ben to finish on The Mall by Buckingham Palace.
The organisers publish area-by-area road information for places including Greenwich, Westcombe Park, Rotherhithe, Wapping, the Isle of Dogs, Canary Wharf, Trafalgar Square and Queen Anne's Gate. The road closures page carries the leaflet, the crossing points and their opening times; the 2027 versions will replace the 2026 details closer to the event.
How do the road closures work?
In the weeks before the race, yellow road closure signs go up along the route. On race day, roads, parking bays and some footpaths along the course close, and police officers and stewards are on hand. Drivers who need to get from one side of the route to the other use designated vehicle crossing points, which open only at certain times as the field passes.
| Your journey | What to expect | Planning tip |
|---|---|---|
| Runner to the start | Start areas in Greenwich and Blackheath, on the far side of London from Buckinghamshire | Leave early, and agree a drop-off point outside the closed roads |
| Supporter at the finish | Roads around The Mall, Trafalgar Square and Whitehall closed | Pick a meeting point away from the finish and walk to it |
| Crossing central or east London | Crossing points open only at set times | Check the published crossing points or avoid the area that day |
| Heathrow or M25 journeys | Not on the course, which runs through central and east London | Plan as normal, but allow for busier roads into town |
How should a runner from Buckinghamshire get to the start?
Very early and with a margin. Greenwich and Blackheath are on the opposite side of the capital, so the journey crosses London on a morning when parts of it are already shutting. Trains from Gerrards Cross, Beaconsfield or Amersham into Marylebone connect to the tube and rail network towards Greenwich, but on the weekend itself check TfL for engineering works and busy services.
A pre-booked car from home removes the changes. Your driver plans the approach around the published closures and sets you down at a point you can walk from, so the only thing on your mind is the race. We run 24 hours a day, so a pre-dawn pick-up is routine: our guide to early-morning transfers explains how we handle very early starts.
How do supporters meet their runner afterwards?
The finish on The Mall is inside a large closed area, and thousands of families try to find their runners at once. Choose a meeting point in advance, several streets away from the finish, and agree it with both the runner and the driver. A tired runner in a foil blanket will be glad of a short walk to a car waiting outside the closures, rather than a crowded train home.
Groups of supporters with banners, bags and a change of clothes for the runner fit comfortably in a Mercedes-Benz V-Class, which seats up to seven.
Plan Your Marathon Weekend Car
What if you just need to get across London that weekend?
Check the published closures and crossing points first, then either travel early before the roads shut or wait until they reopen. With two race days in 2027, a journey you might have moved from Sunday to Saturday could now face the same problem on both days. Journeys that stay west of central London, such as trips from the Chilterns to Heathrow, are not on the course, and our Heathrow guide covers those runs.
Can you book a car for both days?
Yes. If one runner is on the Saturday and a partner or friend on the Sunday, or supporters are going to both, we can plan separate journeys for each day. The fare for each is fixed before you travel, so closures and diversions do not change the price; our guide to fixed-price and metered taxis explains why that matters on a day like this. For another spring event on London's roads, see our Boat Race travel guide, which falls two weeks earlier in 2027.