Island-hopping in Greece is one of the best European travel experiences. Here is how transport works.
Connect virtually every inhabited island. Book through Ferryhopper or DirectFerries. Highspeed ferries cost 2-3x more but cut travel time in half. Book 2-4 weeks ahead in summer - popular routes sell out.
Aegean, Olympic Air, SKY Express fly between islands and Athens. Athens to Santorini is 45 min, 50-120 euro. Worth it for longer routes where ferries take 8+ hours.
Smaller islands (Mykonos, Paros): local buses sufficient. Larger islands (Crete, Rhodes, Corfu): rent a car or scooter. Avoid quad bikes - hospitals are full of quad-bike tourists every summer.
When arriving by ferry, options are taxi (mobbed at arrivals), hotel shuttle, or walking. Pre-booking saves the scramble on busy islands in peak season.