Athens International Airport Eleftherios Venizelos: For Piraeus itself, take Metro Line 3 toward Piraeus (some airport services require a change at Monastiraki; check the departure board). Allow about 60–75 minutes and roughly €9 on the fare quoted in the evidence. The 24-hour airport express bus is the better fallback for a very late arrival or when rail timing is poor: allow about 90 minutes; the evidence quotes €5.50. Do not pay a private transfer simply because you have a ferry—build in time instead.
Piraeus Metro/Rail Station: This is the useful land arrival point: Metro Lines 1 and 3 meet beside the port, near Gate E6. Central-Cyclades departures are close by; Saronic boats are a short walk away. For Crete, eastern-Aegean and Dodecanese ships, use the free internal port shuttle rather than attempting the long walk with luggage.
Piraeus cruise terminals: Small ships can be roughly a mile’s walk from the Metro; larger berths are farther around the commercial port. Take a licensed taxi or ask at the terminal for the bus toward the Metro. Walking is possible only if you are mobile and unencumbered—the route runs beside heavy port traffic.