In many of the places served by the railway system, away from the main tourist areas, only Greek is spoken. Indicateur des Horaires is in Greek and French. The timetable includes a simple system map, that shows principal stations only. The line from Diakopto to Kalavrita is 750mm gauge. There is also a short section of line in use at Volos.
Trains can be very crowded.
Reservations are desirable and sometimes essential. Reserved seats are not marked as such. Station names are usually shown in Roman script as well as in Greek, but spellings can vary considerably from what may appear in timetables, maps or guide books. The first main line electrification in Greece, from Thessaloniki to Idomeni was formally inaugurated on 27 May 1999. The main line from Athens to Thessaloniki is in course of extensive reconstruction, including doubling, re-alignment and electrification.