This Sunday is the 40th staging of the London Marathon - in rather unique circumstances.
Normally held in April, it was postponed until October because of the coronavirus pandemic.
And instead of 40,000 people - elite and amateur runners - winding their way through the streets of London, the world's best will instead by running laps around St James' Park, while the mass participation race is taking place virtually.
How much do you remember of the previous 39 stagings and how the race, and the city that hosts it, has changed?
The BBC will have eight hours of coverage on Sunday, from 0715 BST and there will be a live text commentary running alongside it. Use #bbcmarathon to send in your stories and pictures on Twitter or send video via this link - We want your virtual London Marathon stories.