The connection with the Athens-Larissa-Thessaloniki standard gauge mainline at Palaiofarsalos had a maximum gradient of 3% between Velestinon and Aerinon.

On 13 May 1882, One year after the annexation of Thessaly to Greece[2] Charilaos Trikoupis (Prime Minister and Minister of the Interior)[3] signed a contract with a representative of Theodoros Mavrokordatos (a banker from Constantinople) for the construction of a 1,000 mm (3 ft 3+3⁄8 in) metre gauge railway from Volos to Kalambaka via Velestinos.

During the hostilities of the Greek-Turkish war, in the spring of 1897, the railway transported numerous troops, both within Thessaly and to the borders, closely cooperating with the Greek Army.

The passenger and freight carriages accommodated and transported the soldiers and wounded of the war, as well as supplies necessary for the Red Cross.

[2] After 1900, the railway took over the handling of the mail of Thessalian towns and villages, speeding up delivery and increasing reliability.

In 1970 OSE became the legal successor to the SEK, taking over responsibilities for most of Greece's rail infrastructure.

[8] In 1926, the Greek state allowed the widening of the line and its extension, but the GES reacted, and the project abandoned.