"Granny Bear" has proved a big hit in Bulgaria since the 1930s steam train returned from retirement, chugging day-trippers through stunning scenery from Sofia to the Cherepish Monastery.
"She is super, the engine, I like it better than a modern one!" said an excited Dimitar Kirilov, 12, taking the trip on the "Baba Metsa" train with his grandparents.
A particular attraction is the luxury carriage used by Bulgaria's former king, Boris III (1918-1943). "So elegant and modest," gushed Rada Gancheva, 58.
The comforting hoots, whistles and puffs of steam trains have proved a big money spinner for Bulgarian State Railways (BDZ), earning it 250,000 euros ($280,000) last year.
"The Vitosha Express diesel train of (ex-communist dictator) Todor Zhivkov will soon be made available also," promised BDZ's chief executive Georgy Drumev.
- Chronic debt -
However, this success belies the dire state of the railways in the European Union's poorest country.
According to a 2015 Boston Consulting Group study, Bulgarian trains have the worst quality and safety record among 25 European countries surveyed.
The number of Bulgarians using trains halved between 2000 and 2015 and the volume of freight is a 10th of what it was in the 1980s, according to Georgy Minchev, of the freight transport association.
Creaking infrastructure and ageing locomotives and rolling stock mean that the average train speed is just 55 kilometres (35 miles) per hour.
The 440-kilometre trip from Sofia to Varna on the Black Sea takes eight hours -- and that's on the so-called "express train".
"We started with a 40-minute delay and it grew to four hours by the time we arrived in Varna, making it a 12-hour journey," said one recent traveller, Maria Damyanova, 48.
Horror stories abound on the internet about people's experiences, particularly in winter when the simplest journey can turn into a nightmare.
"Iron nerves and plenty of food are needed if you want to take the train in Bulgaria," reads a typical social media entry by one disgruntled passenger, Margarit Blagoev, 35.
People are sometimes forced to take extreme measures.
In January, 50 frustrated passengers jumped off their regional train when it was brought to a stop mid-journey and stood on the adjacent tracks in the path of an oncoming express train to make it stop and allow their train to head off first.
- Chinese hopes -
The BDZ is saddled with debts of 240 million euros, hindering investment and renovation.
Obsolete infrastructure and thefts of bits of track and signalling systems make derailments, especially of cargo trains, quite common.
In December, a freight train transporting gas derailed and exploded, killing six people, injuring dozens more and devastating a small village in the north-east.
After failing for years to attract funds, help may be on the way however from China, which is seeking to invest heavily in infrastructure projects in eastern Europe and elsewhere.
The China Railway Rolling Stock Corporation (CRRC) group has pledged to reimburse 130 million euros of BDZ's debts and invest 170 million euros in new trains, according to the Bulgarian transport ministry.
In addition, it has offered to invest 300 million euros in a new train assembly plant. The government is studying the proposals.
But not everyone in Bulgaria is pleased at the prospect.
"This offer will result in a mere restructuring of the debt and to new borrowing due to the BDZ's overindebtedness," said economist Georgy Angelov.
"The project will aggravate the risk of bankruptcy," he said.