There are several buses that leave daily from Athens to Delphi. Most buses have as final destination the towns of Amfissa or Itea and pass through Delphi so that passengers can get off there. The trip takes about 3 hours and buses depart from Liossion KTEL Bus Station in Athens, close to Attiki Square, about 4-5 times per day. If you do not want to travel there independently, you can take an organized bus tour to Delphi from Athens.
Travel to Delphi
Travel to Delphi, Greece: Visitors can travel to Delphi by bus or car. Here is travel information about buses and cars but also useful numbers, pdf guide.
To go to Delphi by car, you take the National Highway from Athens to Lamia and at the junction of Thebes, you follow the signs to Levadia. After Levadia, you continue to Arachova/ Delphi. The road from Athens to Thebes is large and comfortable, while the road from Thebes to Delphi is rural, which means that it has only one line per direction. The road trip from Athens to Delphi is about 3 hours.
Useful numbers in Delphi: police station, hospital, taxis, bus services, museums, and more