How long does it take to cover 125 km? In a mountain range such as the Rhodope this is a difficult question. Even Bulgarian drivers who like to fly along roads as if they were exempt from the laws of physics have to slow down a bit along the winding roads of the Rhodope.

The Septemvri-Dobrinishte narrow gauge railway redefines the concept of slow travel. It takes the 125 kilometre long route in... 5 hours.

For travellers and holidaymakers, the narrow gauge railway is a blessing. The only railway of this type in Bulgaria provides an excellent opportunity to pass through some stunning landscapes without having to hurry. In some areas the train trundles along so slowly that people can actually hop off and hop on again at the next turn.

However, the Septemvri-Dobrinishte narrow gauge railway is not just a tourist attraction, though the Bulgarian State Railways company sometimes schedules purely recreational trips with a steam engine and pre-war cars. The railroad is of vital importance to the locals because for some of the villages in this part of the Rhodope it is the only mode of public transport. So, in the narrow gauge carriages you will meet a unfiltered assembly of locals: elderly Pomak women who carry huge sacks, students going home for holidays, men who have been shopping in one of the bigger towns. In fact, a journey with the narrow gauge railway may be the best way to meet Rhodope people without entering their homes.

That the narrow gauge railway is old can be seen in the frayed cars and locomotives.

The idea for the narrow gauge railway to go through the western Rhodope and all the way along the Mesta river to Nevrokop (now Gotse Delchev) dates back to the post-Balkan wars period. In 1912-1913 Bulgaria incorporated the region in its kingdom. There were no modern roads in the Rhodope at the time and the Bulgarian state needed infrastructure badly. Industry and trade required fast and cheap transportation, and so did the military as the prospect of war in this part of the Balkans remained realistic.

In 1915 the government started exploring the options to construct a railway along the Yadenitsa, Chepinska and Vacha rivers. A year later the route had already been agreed upon: from Saranbey (today's Septemvri) to Nevrokop. At that time Bulgaria took part in the Great War and engaged in combat in the Balkans – hardly a time to start building a narrow gauge railway. So, the project was shelved until 1920.

Bulgaria, a defeated nation in the Great War, impoverished and teaming with refugees, had to pay reparations to the Allies. In addition, it was banned from maintaining viable armed forces. The Saranbey-Nevrokop narrow gauge railway project was considered a way to overcome the economic crisis. Construction started in 1921, mostly by "labour troops," an ingenuous if not very democratic way for the government to conscript free labour and at the same time maintain an army exceeding its First World War mandated quotas.

Five years later the railroad reached Ludzhene, one of the villages that would later make up Velingrad – roughly midway between Saranbey and Dobrinishte. The construction works so far included 10 tunnels that were dug using just dynamite. The first train departed in 1925.

The construction effort continued. It took nine years to complete the Avramovi Kolibi stretch. At 1,267 metres above sea level today's Avramovo station is the highest elevation railway station in the Balkans. The Bulgarian engineers in charge had to make the railroad in figures of eight to overcome the steep hills. In the course of 9 kilometres there are 15 tunnels. After Avramovo, the railroad starts ro descend until it reaches the Mesta valley.

When the stretch to Belitsa – a village between the Rhodope and the Rila – was finished, in 1939, the first train arrived with a special driver, King Boris III.

Two years later Bulgaria joined the Second World War on the side of Nazi Germany. It hoped it would be able to regain territories like todays' North Macedonia and Aegean Thrace it had either lost in the Great War or considered ethnically and historically Bulgarian. Construction of the narrow gauge railway continued up until 1945, when the line reached Dobrinishte, south of Bansko. But then the works ceased. Thirty years after the initial project was approved it became increasingly clear that there were cheaper and more viable alternatives to rail transport. The idea to construct a second narrow gauge railway through the central Rhodope never kicked off.

Travelling the Septemvri-Dobrinishte line and back can be done in a day, and will easily became a highlight of your trip in the Rhodope – or in Bulgaria.