Have a look at Pat Rhys-Jones' article about her 2004 holiday in the Balkan Peninsula (pdf). Her travels took her through Slovenia, Croatia, Bosnia, Montenegro, Kosovo and Macedonia.
Here is how Pat introduces her article: "In September 2004, Les and I set off to travel through Europe. Our journey began with our son, Grant, and his wife, who were living and working in London. Grant introduced us to his friend Alon, who was living in the Netherlands, and he kindly assisted us in purchasing a small mobile home. We travelled through many European countries and, whilst in a caravan park in Hungary, we met an English couple who could speak Dutch. They read our green card and advised us that our green card allowed us to travel into Bosnia and Kosovo; the radar went up and away we went."