Buses: Varies. Generally not very accessible, but newer buses on major routes will have a space for wheelchairs and a lift, but whether these are actually used in practice is uncertain. Long-haul buses in Greece are usually tour-type buses with elevated seats, on-board toilets, window curtains, and other amenities. But access is almost always up a narrow flight of steps.
Trains: Access to cars is almost invariably up narrow steps. Buses are more likely to be accessible, and tend to be faster and more comfortable as well.
Ferries: Accessibility varies dramatically. Problems usually consist of unexpected steps up or down onto a deck and narrow passages. Private cabins are often very small and tight. Bigger, newer boats will have better facilities.
Hydrofoils: Accessibility varies. The bigger hydrofoils offer better accessibility. The small ubiquitous island-hoppers will have limited accessibility and usually steps down into the body of the boat.
Catamarans: These bigger vessels tend to be the better bet for handicapped travelers. Where they are available, they are usually the best sea-travel choice for the handicapped traveler, with airplane-like cabins but with more room.
Sidewalks: Often uneven, rarely have curb cuts, few drivers pay much attention to the lights. Also a nightmare for parents with kids in strollers - see Matt Barrett's cautionary classic "Strollering Through Athens" under Travel with Kids to get an idea of this very challenging aspect of Greek travel.
Athens Airport: Good access in the terminal including marked bathrooms. Unfortunately, steps are the rule for deplaning areas. Electric cars are available for disabled passengers to transfer between the two terminals.
Athens Metro: Okay access including marked bathrooms. The new Metro initially ignored physically-challenged users, but Greek disabled organizations forced the plans to be revised, with some success.
Rental Cars: Most major international companies will offer adaptive equipment but require an advance notice. Some Greek companies do as well, but you may be in for an easier time of it with the multinationals.
