I mostly travelled by train when in Slovenia, Croatia & Serbia, providing me with ample opportunity to ask fellow travellers to draw their countries.
On my train from Ljubljana to Zagreb, I asked Fredi to draw Slovenia for my collection. He did (in miniature), and a few minutes later, presented me with lots of tourist destination business cards "for my collection". I had absolutely no use for these, but it was a lovely gesture nonetheless.
On the long and slow train from Zagreb to Belgrade, I met Klaus who, despite the German name, was Croatian. I started speaking to him when, at the Serbian border, I thought I had to get off the train. I didn't, and Klaus, a fellow Eurovision visitor, set me right. Klaus drew Croatia, and apparently stole some land from Slovenia, he said with a giggle.
Later in the trip, Marina from Serbia joined us in the compartment. Marina studies in Berlin, and was amused but pleased by us Eurovision travellers. When I asked her to draw Serbia, she joked about whether she should be politically correct or not. I sighed with relief that she thought it a joke - she has included Kosovo in the map.