The network of Thessaly Railways consisted of the following lines: Construction started in 1882 under the general management of chief engineer Evaristo de Chirico.

The section from Volos to Larissa, 61 kilometres (38 mi) long, was inaugurated on 22 April 1884 by King George I.

The standard gauge line is physically connected to the Athens-Thessaloniki mainline, allowing OSE to run through services to Volos from Athens and Thessaloniki.

Freight traffic declined sharply when the state-imposed monopoly of OSE for the transport of agricultural products and fertilisers ended in the early 1990s.

This section is maintained by the Museum Railways Company or EMOS (Greek: Εταιρεία Μουσειακών Σιδηροδρόμων or ΕΜΟΣ).

EMOS preserves a variety of rolling stock owned by the Hellenic Railways Organisation under long term loan.

In addition, the old single line passing through Tempi Valley, which was cut off from the mainline when new tunnels were constructed, is used as a tourist attraction with light railway vehicles.