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"Elite races for men, women and wheelchair athletes will take place on an enclosed looped course in St James’s Park in a secure biosphere (a contained safe environment like that of Formula 1 and England cricket) and times will be eligible for Olympic qualification.
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Everyone with a place in the 2020 event will still have the chance to take part in The 40th Race by running the famous 26.2 mile marathon distance from home or anywhere in the world on the course of their choice. All finishers will receive the coveted finisher medal and New Balance finisher T-shirt. In addition, all runners and charities will also be able to defer their place to a future London Marathon – in 2021, 2022 or 2023.
In 2021, the London Marathon will move from its usual April date to Sunday 3 October to give the best chance for the mass race to return in 2021."