Hellenic State Railways
| Chemins de fer de l'État Hellénique | |
| Overview | |
|---|---|
| Headquarters | 1–3 Karolou St., 104 37, Athens |
| Locale | Greece |
| Dates of operation | 18 March 1920–31 December 1970 |
| Successor | |
| Technical | |
| Track gauge | 1,435 mm (4 ft 8+1⁄2 in) 750 mm (2 ft 5+1⁄2 in) |
| Previous gauge | 1,000 mm (3 ft 3+3⁄8 in) 600 mm (1 ft 11+5⁄8 in) |
| Length | 302 km (188 mi) |
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Hellenic State Railways or SEK (Greek: Σιδηρόδρομοι Ελληνικού Κράτους, Sidirodromi Ellinikou Kratous; Σ.Ε.Κ.) was a Greek public sector entity (legal person of public law, Greek: Ν.Π.Δ.Δ.) which was established on 18 March 1920 by the law 2144/20 and operated most Greek railway lines until 1970.