Map of Attica in Socrates and Plato's time
Nice map of Attica, Boeotia, and Euboea with their cities. Depending on the context, Athens may refer to the city of Athens proper, exclusive of its suburbs such as Piraeus, its main harbor, or the larger urbain area including such suburbs as Piraeus, or the whole of Attica, the territory of the "city-state", in which most of its citizens would live and own land, or even the whole of the Athenian empire that spread all through the Mediterranean, grew and shrunk over the years (the same could be said with little variation of all the "city-states" of ancient Greece, such as Sparta, Thebes, Corinth, etc.). Thus, what were called citizens of Athens, were in fact people living all through Attica, not necessarily in the city of Athens itself, though they all had to go there from time to time to accomplish their civic duties.
Read More about Map of Attica in Socrates and Plato's time