Sleeping car

Anticipating the surge in holiday travel, the Bulgarian Railway Company, "BDZ - Passenger Transport," is set to accommodate the festive influx by providing an additional 17,000 seats for travelers during the Christmas season.

Night trains have made a comeback in Europe thanks to their low-carbon footprint, but after years of neglect, the renaissance has had a bumpy ride.

Operators admit that the trains are outdated - with passengers facing the occasional delays, technical problems or malfunctioning toilets - while companies compete in an overloaded network.