University Press
University Press: Ancient Greece
Exhaustive and informative collection of information on ancient Greece arranged by topical area: art, architecture, history, the Olympics, wars, geography, mythology, people, and more.
Other
Sweet Briar College: Athenian Acropolis, Greece
An explanation of the term "acropolis" as well as a description of how the acropolis was used in classical Greece. Also contains extensive information about the Parthenon and Erechtheum, which were built on the Acropolis.
PBS
Pbs: Why Did Greece Develop City States?
This site from PBS gives three explanations for the development of city-states in ancient Greece.
Friesian School
Friesian School: Origin of Philosophy: Why the Greeks
This resource gives an intense discussion of how the geography and trade patterns of the ancient Greeks may have influenced the development of their philosophy.