Ferries
The ferry network is the heart of Greek travel. To reach the islands, you will mostly take a ferry — and Greek ferries run to a schedule, so arrive at the port at least an hour before departure (an hour and a half if you have a vehicle). In August, ferries fill up quickly around the Assumption holiday (15 August), so book ahead.
Piraeus, just southwest of Athens, is the main port and the busiest in the Mediterranean. Most ferries to the Cyclades, Dodecanese, Crete, and Aegean islands depart from here. Rafina, on the eastern coast of Attica, is a smaller and often quicker option for northern Cyclades destinations like Mykonos and Andros, and also serves Lesbos and other northern Aegean islands.
High-speed catamarans cut journey times roughly in half at about double the price. The slower conventional ferries are cheaper, often overnight, and let you bring your car. For island-hopping in summer, booking a few days ahead is wise; for August, book as far in advance as possible.
Ferry schedules and tickets can be booked through Ferryhopper or Greek Travel Pages, which list all routes and connections.
Buses (KTEL)
KTEL is the national intercity bus system — a network of regional cooperatives that together cover virtually every corner of the country, including remote towns and villages that trains do not reach. Fares are low and the buses are generally air-conditioned and reliable.
From Athens, KTEL Kifissou station serves the Peloponnese and western Greece; KTEL Liossion station covers central Greece, Thessaly, and the north. There is no single national booking site — each regional KTEL company runs its own website or ticket office.
Trains
The rail network, operated by Hellenic Train, is limited compared to northern Europe but has improved considerably. The Athens–Thessaloniki intercity line (around 4–5 hours) is the most useful for travellers. Trains do not serve the islands. Tickets can be booked at Hellenic Train.
Driving
Having a car opens up the mainland significantly — the Peloponnese, Epirus, Halkidiki, and the mountain regions are all much easier to explore by car. Greek roads have improved dramatically since the 1990s; the main motorway network is excellent. Driving in cities, especially Athens, is chaotic and parking is difficult. On many islands, renting a small car or scooter is the standard approach.
Greece has one of the higher traffic fatality rates in the EU. Speed limits are regularly ignored by locals. Drive defensively, especially at night and on mountain roads.
Flying Domestically
Olympic Air and Sky Express run frequent domestic flights between Athens and the islands. If you are short on time, flying to Crete or Rhodes rather than taking an overnight ferry saves a day. In summer, island airport slots fill quickly — book ahead.