It incorporates the former Athens-Piraeus Electric Railways (ISAP), which opened as a conventional steam railway in 1869, was electrified in 1904, and is now part of Line 1.
Metroen inkorporere den tidligere Athens-Piraeus Elektriske Jernbane (eller ISAP), som åbnede i 1869, elektrificeret i 1904, og er nu en del af Linje 1.