At the outbreak of the Peloponnesian War, the Athenians allowed the founding of a sanctuary for the Goddess Bendis and shortly afterward created a state festival, the Bendideia, for her.The first celebration was held on the 19th of Thargelion (May–June), 429 bc, at the Piraeus, the seaport of Athens. Many pagan calendars list June 6th as the modern equivalent date for this festival honoring the Moon Goddess of Thrace. Other sources give that her festivals were held on the full moon preceeding or coinciding with the solstice - and if so, the dates would vary from year to year.
For a description of the festival we have this excerpt of a conversation between Socrates and a friend describing that festival (from Plato's Republic)...
... I am so sorry to do this to you, but this post has been moved to my new website, The Pagan Calendar, and can be found in its entirety here: The Bendideia of Bendis
As you explore this site, you may find links to a "page not found" instead of something cool and magickal. For this I apologize. I am very working hard behind the scenes to restore those pages along with a link to their homes on my new website where they can be viewed in full.