It was the 19th Century poet, Robert Browning, who popularised the German story of the Pied Piper of Hamelin in the English-speaking world.
The real piper arrived in 1284...
His poem tells of a strange musician in multi-coloured clothes who promises to free the town of Hamelin from its plague of rats. With his pipe he lures the rats to the river, where they drown. But when he returns for his money, the town refuses to pay up.
Again he puts his pipe to his lips and plays. But this time it's the children he seduces. Swallowed up by a fantastical cavern, they are never to be seen again.
The setting of this fairytale - Hamelin, or Hameln - is a real town in northern Germany, near Hanover.
So if Hamelin is real, could the figure of the Pied Piper be real too?
It's a question that's preoccupied many scholars over the years, as well as the children's poet and broadcaster Michael Rosen. He set off to Hamelin to find out - accompanied by a modern day Pied Piper, otherwise known as Michael Boyer from the town's tourism office.
The tale of the piper has drawn tourists to Hamelin for more than 300 years, but the story actually dates back to 1284. According to an eye-witness account, recorded in Latin at the time, it was the 26 June when "130 children were taken from the town by a piper dressed in many colours".
This story is also written on the wall of Pied Piper House in Bungelosenstrasse (drumless street) - the street where the children were last seen and where, to this day, no music can be played out of respect for the lost children.
So, it seems there is firm historical basis for the piper. But what about the rats?
Modern Hamelin is full of rats - from pretzel-rats and chocolate rats, to the rats painted on the cobbles that guide tourists in the footsteps of the piper.
...his story is still told today...
But this part of the story was actually added in the 16th century. And it was around that time that the "bunting" or "colourful" piper became known as the "Rattenfaenger" - the Ratcatcher.
Michael Boyer believes the name change happened for a reason.
"The entire business of the rats could be an attempt to wash out the bad memories," he says. "It could be a cover-up, to draw attention away from the business of the children and make it all so sugar-coated and so mysterious."
The rats may be a red herring, but in the medieval mill-town of Hamelin they were certainly a problem. And not the only one. In 1284 at least 90% of the population of this busy town were living in extreme poverty, starving and struggling to feed their families.
This has led Elke Liebs, a professor in German literature at Potsdam University, to an unsettling conclusion about what really happened.
"From the Middle Ages on you see these chronicles where the parents send the children away - like in Hansel and Gretel. All these stories hide the real background, that the parents were glad to get rid of the children," he says.
...and Hamelin tourism office makes sure the legend lives on
Some theorists think the children were led out of the town because they had the plague, others believe they were victims of the dancing illness, St Vitus' Dance, or were led off in the children's crusades.
One theory has it that the children went willingly to partake in Pagan rituals on the Koppen mountain a few miles outside the town.
But the most widely accepted theory links the loss of the children to a 13th century migration from the Hamelin area eastwards.
Professor Juergen Udolph speculates that, with new lands to settle, feudal barons sent a brightly coloured "recruiter" into Hamelin with a pipe and a drum to draw the young away.
"He said - you have a new chance in a new land. Please, come with me."
Whatever the truth of the story, experts in myth and fairytale believe it reflects our preoccupation with the fear of losing children - whether to a stranger, or to death.
An inspiration for film and poem, the story has held our fascination for more than 700 years - and is likely to cast its spell for 700 more.
Losing the Children is broadcast on BBC Radio Four on 19 February at 1530 GMT. It will also be available through the BBC Radio Player.