Paul Elliott and Laura Harvey decided to combine their love of running and each other and have their big day mid-race.
The courageous couple will run 13 miles, before exchanging vows in front of their 80 guests.
They will then finish the last 13.2 miles, before trading in their trainers for their party shoes at their reception.
This will be the second time Laura has run the London marathon - talk about putting us to shame! - and will be swapping a traditional wedding dress for a tennis gown. Paul will be accompanying her in a suit top, leggings and a top hat.
The pair are running for Cancer Research UK, as Paul's father sadly past away from bowel cancer 19 years ago. Laura and Paul aim to raise £5,000 to help the cancer charity hit this year's £2.5 million target.
Laura, 34, said: "We both love the London Marathon and wanted to do something different for our wedding. We thought it would be amazing to combine the two! We got engaged last May and are very grateful to Cancer Research UK and London Marathon for helping us make this happen this 2015."
Have a fab day, guys!
By Hannah Carroll
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