With three or more lanes in each direction, it is highly accommodating, but sometimes it gets jammed. This happens more often during the nights of summer months, when it becomes one of the epicenters of the Athenian nighttime Entertainment.
To get around on the long (about 25 km) Poseidonos Avenue there is a very good alternative - the Athens Tram. The tram runs the entire Poseidonos Avenue to Voula. The beautiful line is right on the coast.