The Slovenia-Slovakia mixup
As is well known, Slovenia and Slovakia are often confused by outsiders. See the excellent (and often very funny) series of posts on this subject on The Glory of Carniola.
Well, recently I've had my first direct experience with this phenomenon, when a book I had ordered from a seller in the U.K. reached me with a few days' delay. As the stamp on the envelope shows, after leaving England on November 6, the book reached Bratislava, Slovakia on November 9. From there it was redirected to Slovenia and reached me a couple of days later.