Република България 1988
My first holiday by myself - 18 years old - was to Bulgaria, the most exotic destination I could think of and afford on my budget. I took a train to the north of Greece and crossed the border to Bulgaria at Kulata/Кулата. Prerequisite for a visa was a reservation for a certain number of nights with a state-approved landlord or hotel. For all other nights a stamp for each night had to be collected on a card.
1988 was the year before the Communist Party was forced to give up its political monopoly in November 1989 and in the parks of the capital Sofia there were anti-government protests. It appears the protests originated in Ruse in November 1987 against the gassing and protecting fundamental human rights.