I'm coming to Athens for 4 nights next month & just wondered if anyone could clarify one or two things about the underground metro system for me? I've read in a couple of places that Metro travel is free for disabled people, but others have suggested that it's only for Greek resident disabled people and/or that you may need to provide certain documentation to "prove" your disability. Other places have even suggested if you're disabled, you don't even need to buy a ticket of any kind of the Metro and can just use it at will without any form of ticket.
Could anyone who knows for sure just clarify the situation for me? I've heard there are pretty hefty fines for getting things wrong when it comes to tickets, so I don't want to make any honest mistakes!