Santa Claus' very own post office is located at the Arctic Circle in Santa Claus' Village in Rovaniemi in the Finnish Lapland. This is where children from all around the world send their wishes and letters to Lapland's Santa Claus every year. Santa and the elves have an enormous job in handling all the letters and making sure that the packages and letters sent from the Arctic Circle in Rovaniemi are properly stamped.

Useful links:
The Official web site of Santa Claus main post office in Rovaniemi at Arctic Circle (Lapland, Finland)
Rovaniemi in Lapland in Finland official tourism information