1. The airport is 38 kilometers from the city center. You can reach it either by taxi (45 euros) or by underground (8 euros), in 45 minutes. From the airport, you can go directo to Peireus, if you would like to find the port to the islands. Cost day time (05:00-24:00) 45 € - Night (24:00-05:00) 65 €.
2. Hot points in Athens.
In the morning:
- Acropolis / Parthenon, you need 2,5 hours.
- Theatre of Dionysos + ancient market + Temple of Zeus/ 2,5 hours. (for me ancient market is more interesting thna Partenon).
- archaeological museum/3 hours.
- Arcopolis museum/3 hours.
At the afternoon: Two afternoons:
- day one: Visit "Plaka".
- day two: Visit Peireus, the golf "Zea".
- day one: In Kolonaki, close to Syntagma squear.
- day two: "Keramikos place", you can go by underground.
Some athenean bests:
Best lunch. Plakiotissa, close to Acropolis.
Best coffee. "Kafe Raki". Close to Acropolis, 82 Dimitrakopoulou street.
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In case you are in the airport, and you have 4 hours available, visit "Sounio", where in the temble of Poseidon. The best sunset in Athens!!