Various diesel locomotives – BDZ 790 series (710kW) and 770 series for regular service; historic steam locomotives occasionally deployed on special tourist runs
Locomotive Weight
~60 tonnes (BDZ 790 series diesel)
Track Gauge
760 mm (2 ft 5 15/16 in) narrow gauge
Braking Technology
Vacuum brake system with traditional railway knuckle couplers
Route Engineering Challenges
35 hand-bored stone tunnels through mountain rock
Multiple figure-eight spiral loops for altitude gain
125km single-track with limited passing loops
Avramovo station at 1,267m – highest railway station in the Balkans
Steep gradients up to 30‰ through river gorges
Legacy maintenance of 1930s-era bridges and viaducts
Line length
125 km (78 miles)
Journey time
5–5.5 hours one way
Opened
1936 (fully operational)
Status
Operational – only surviving narrow-gauge passenger line in Bulgaria
Track
760mm gauge, single track, 35 tunnels, multiple viaducts