Each year, Sweden's postal service receives an overwhelming influx of thousands of letters commencing with the words "Dear Santa." Not only does it diligently respond to each one, but it has also maintained a collection of these letters that have stood out for more than a century.
With addresses such as "Lapland," "Reindeer Land" or "Santa's Igloo," the postal service PostNord last year alone received around 16,000 letters intended for Father Christmas.
A few letters every year are selected for the museum's archives, a collection that now holds about 10,000 letters from around the world, the oldest dating back to the 1890s.
"These are from the U.S., from Asia, I have some here from Taiwan," Kristina Olofsdotter, head of stamps at PostNord, tells Agence France-Presse (AFP) at the Postmuseum in Stockholm.
Toys, pets and books have topped children's wish lists over the years, as they do today - though children of yore were perhaps a little more modest in their expectations.
"You can see that in the old letters, the kids asked for maybe one or two things, nowadays there are longer lists," Olofsdotter said.
Many of the letters, written in children's handwriting, also have questions for Santa.
"What is your favorite drink so that we know what to put out for you?" one young girl asked in the 1960s.
A 4-year-old wanted to let Santa know she had just learned to write her name while adding: "I hope your reindeer are well."
All of the letters are opened and read, and when a return address is provided, the museum sends a reply back.
Olofsdotter said the reply typically "says 'Hi from Santa,' with thanks for the letter. And he says that he has got a lot of work to do up until Christmas and that he really appreciates the letter."
She says the return letter also encourages kids to brighten somebody's day by writing them a letter, and "to not forget that all your dreams can come true if you believe in yourself."
And it is not only children who send letters to Santa Claus: This year's batch contained a letter from Taiwan sent by a 20-year-old.