ThemarathonwasNOTaneventoftheancientOlympicgames.ThemarathonisamoderneventthatwasfirstintroducedintheModernOlympicGamesof1896inAthens,aracefromMarathonnortheastofAthenstotheOlympicStadium,adistanceof40kilometers.

　　TheracecommemoratestherunofPheidippides,anancient"day-runner"whocarriedthenewsofthePersianlandingatMarathonof490B.C.toSparta(adistanceof149miles)inordertoenlisthelpforthebattle.AccordingtothefifthcenturyB.C.ancientGreekhistorianHerodotus,PheidippidesdeliveredthenewstotheSpartansthenextday.

　　Thedistanceofthemodernmarathonwasstandardizedas26miles385yardsor42.195km.in1908whentheOlympicGameswereheldinLondon.ThedistancewastheexactmeasurementbetweenWindsorCastle,thestartoftherace,andthefinishlineinsideWhiteCityStadium.