Around this time of year, 2,502 years ago, the Athenian phalanx defeated a much larger Persian expeditionary-force at the Battle of Marathon. And so, to commemorate this achievement, hundreds of thousands of Americans will run 26.2 miles and call themselves “marathoners.”

But really, they’re not commemorating the battle; they’re commemorating the run that followed. After the victory on the plains of Marathon, the Athenians sent a messenger back to Athens to bring the good news. The runner quickly covered the 26.2 miles between Marathon and Athens, alerted his countrymen that they need worry no longer, and then died of exhaustion. It’s a very romantic tale. Too bad it’s not true.

The tale above was probably invented more than 500 years after the battle in an attempt to make a dramatic event just a little more dramatic. Still, the actual story of the first marathon run is amazing even though no one dies with victory on his lips. The Greek historian Herodotus recorded the events surrounding the battle, and he explains that the Athenians were quite nervous when they heard that the Persians were on their way. The Athenians decided to ask the Spartans for help because the Spartan phalanx was the most powerful military force in the Greek world. They entrusted their message to a professional runner named Pheidippides, who left Athens one day and entered Sparta the next, covering a distance of 150 miles. Poor Pheidippides ran in vain, however, because the Spartans were busy with a religious festival. Though the run didn’t achieve the desired result and no one sacrificed his life, Pheidippides’s run is still remarkable. Professional couriers routinely made these ultra-long-distance runs, but Herodotus tells us about Pheidippides’s achievement because of the unheard of speed with which he covered these 150 miles. According to Herodotus, though, he had some divine help. Pheidippides claimed that the god Pan paced him during a rough spot on the grueling run and that Pan asked Pheidippides why the Athenians didn’t give him enough worship. After hearing this story, the Athenians got a little more serious about Pan.

Marathoning, as a sport, began at the first modern Olympic Games in 1896. The organizers wanted to spice up the games so they recreated the run from Marathon to Athens. The winner, a Greek runner, won the 25 mile long race in a little less than three hours. Yep, that’s right 25 miles. The first 26.2-mile marathon was run at the 1908 Olympic Games in London because the distance from Windsor Castle to the stadium was 26.2 miles. (This is merely one instance in which our modern Olympic Games tell us more about turn-of-the-century Brits than about ancient Greeks.) So, if you’re running a marathon this season, when you hit the wall, you can curse the British for that extra mile you’re going to have push through. But while you’re at it, you should probably also be thankful that the race organizers got their legend wrong and you’re not running 150 miles.