The first public railway in Bulgaria opened on 7th November, 1866, when the country was part of the Ottoman Empire. It ran from Ruse to Varna, a distance of 223km and was built to standard (1435mm) gauge.
In 1888, a decade after Bulgarian independence, the recently formed State railway company took over all existing railways and was to exercise control over all new railways in the country into the 21st century.
Although the majority of lines in the country were constructed to standard gauge, a number of narrow gauge lines of 600mm and 760mm gauge were also constructed. These were, however, treated as an integrated part of the state network. Just one such line remains in operation: a 125km, 760mm gauge line running from Septemvri (where there is interchange with the standard gauge network) to Dobrinishte in the Rhodope Mountains.
Flag image from CIA World Factbook