Today is not only Marathon Monday but also Patriots Day in Boston, which hosts the world's oldest annual 26.2-mile run. The Boston Marathon dates back to 1897, when 15 runners – all men – started the race. Only 10 reached the finish line. In 1966, Roberta "Bobbi" Gibb became the first woman to run and successfully complete the race, but it wasn't until 1972 that women were officially recognized as part of the field. More recently, just 10 years and 2 days ago, Paula Radcliffe set the women's marathon world record at the London Marathon when she finished in 2 hours, 15 minutes and 25 seconds. No woman has come close to topping that time since. Last year's top female finisher in Boston -- Kenya's Sharon Cherop -- crossed the finish line in 2:31.50.