Gemaess UPU, vatikanische Poste ist einer der bester organisierten Post in der Welt.

Many Romans, distrustful of the unreliable Italian post office, make weekly trips to the Vatican just to post their important letters. Italian stamps may not be used on Vatican mail nor vice versa. According to the Universal Postal Union, the Vatican post office is "one of the best postal systems in the world" and "more letters are sent each year, per inhabitant, from the Vatican's 00120 postal code than from anywhere else in the world.

Gruss.
Mariusz