Piraeus is a rather chaotic place with traffic that's horrendous even for Greece. Particular caution should be used when crossing the street, or when walking along the pavement by the ferry quays where cars, taxis, and trucks often drive randomly among the crowds of travelers walking to and from the boats.
Piraeus is a huge port filled with sailors, and parts of it are about as tough as you'd expect such a place to be. The areas right by the ferry quays are safe enough, but avoid wandering around the rest of Piraeus, especially at night, unless you know your way around.
Unlicensed taxi drivers often meet arriving ferries. Unlike in some countries, these taxis have a bad reputation and should not be considered as a cheap alternative to licensed cabs.
Pickpocketing gangs have been reported working on the Piraeus-Airport bus; for a full description see the Athens Stay Safe section.
One scam you may encounter in Piraeus is a rather subtle one. A man will walk up to you while you are waiting with your luggage in line to board a ferry. This gentleman is a consummate actor: though he doesn't actually claim to be working for the boat or port, his demeanor and behavior imply strongly that he is. He'll pick up your luggage, brushing aside any objections, and usher you with it to the head of the line, at which point he'll demand a hefty tip. In one reported case the bite was â¬7.00 our respondent decided the performance was worth â¬2.00