Paula Radcliffe smashed the women's world record at the London Marathon on April 13, 2003.
The British star was already the record holder having set a new best of two hours, 17 minutes and 18 seconds in Chicago in 2002 – her first year stepping up to the distance.
She had also won the London Marathon in 2002 in a record time for a women's only race but wanted to push the boundaries by using male pacemakers.
The tactic earned her criticism but Radcliffe seized her opportunity spectacularly by completing the course in 2hrs 15mins 25secs, dominating the race from start to finish.
Radcliffe, then 29, said: "Everyone said that London could not be a fast course. But I knew from last year it was.
"We got a good day, and the wind was behind us more than it was in front – and we have proved it is a fast course.
"I was trying to stay relaxed until halfway and then just keep it going. But it was really tough in the last five (miles).
"There was a lot of pressure, and people were talking about the times I was going to run.
"I went through halfway way faster than I had planned to even if I felt good. But I thought, 'You've committed, so you just have to hold it'."
Radcliffe held the record until 2019, when Kenya's Brigid Kosgei ran a blistering time of 2:14:04 at the Chicago Marathon.