Krakow Letter: At the top of the hour, every hour, night and day, Krakovians hurrying through the medieval town square stand still, look up to the towers of the Church of the Virgin Mary and wait.
Without fail, a window opens in the taller of the two towers, a shiny trumpet sticks out and an invisible trumpeter begins to play the Hejnal or Hymn to Our Lady.
The trumpeter moves to three other windows in the 81m (266ft) tower and, after playing the Hejnal to the four winds, closes the window to applause from the crowd gathered below.
The first historical record of a Krakow trumpeter comes from 1392 and concerns a fireman paid by city authorities to announce the closing of the city gates every evening and to keep watch for fires, a common occurrence in a town built of timber.
Before that, legend has it that one day in 1241 the trumpeter in the tower was horrified to see a horde of Tatars from the east charging towards the city.
Rather than waste precious time bolting down the stairs to warn the citizens, the trumpeter played the Hejnal over and over until the Krakovians got the message.
The warning gave them time to grab their crossbows, take their positions on the city walls and see off the invaders - but not before one of the Tatars landed an arrow in the throat of the brave trumpeter, ending his career - and the Hejnal - mid-note.
What few locals or tourist- guide authors realise is that this legend they retell was popularised by Eric P Kelly, an Irish-American college professor and author of the popular children's book The Trumpeter of Krakow.
Kelly was born in Amesbury, in Massachusetts, on March 16th, 1884, and worked as a journalist and then a journalism professor at Dartmouth College.
He wrote short stories and half a dozen books, mostly about the culture and history of Poland, and won the Newbery Medal in 1929 for The Trumpeter of Krakow.
The book, still in print today, tells of Joseph Charnetski, a 15- year-old Ukrainian peasant who arrives in Krakow in 1461. He is soon caught up in an adventure to protect a famous jewel from being stolen for a Russian czar.
Kelly works into his book the trumpet tradition that was revived in Krakow in 1810 after falling dormant for centuries.
He didn't come up with the idea of linking the trumpet tradition to the attempted Tatar invasion of 1241: that had already happened in the early 1920s.
It was Kelly's 1928 book that promoted this version of the story, told to this day by all Poles - including Zbigniew Ojczyk, a musician and trained fireman who has been a trumpeter in the tower since 1994.
"There are no documents to confirm the legend, but behind every legend is some truth," he says in the tower room, a cramped space of wooden beams and plaster walls that has remained largely the same for the last 500 years.
Along with five other firemen, he carries on the hourly tradition that continued right through the second World War and the communist era.
The trumpeters work in teams of two, each playing for six-hour rotating spells over a 24-hour shift.
The noon bugle call has been carried live by Polish radio since 1927 and there are few attempts to tinker with the hourly repertoire.
When Poland joined the EU two years ago, the trumpeters followed up the Hejnal with Ode to Joy. When Pope John Paul II died last year, they played the song Mother's Tears at 9.37pm - the time of his death - on the first Saturday of every month for the following 12 months.
After 12 years, Zbigniew says he hasn't tired of what must be one of the world's most secure musician's jobs, nor has he ever missed an hour.
"It's sometimes happens that someone has overslept, but not me," says Zbigniew.
As 1pm approaches, he puts on his cap, rings the bell, unpacks his trumpet and heads to the window.
Four minutes and four Hejnals later, he looks down at the crowd gathered below with a laugh and a wave.
"Someone once said I wave like the pope!"
