It is difficult to figure out which day best corresponds with a date on the ancient Greek calendar. There are a few reasons for this including the fact that each polis might use a different calendar. This page on the festivals of ancient Greece explains some of the problems we face even with the calendar of ancient Athens:
Greek Months. It won't tell you everything, but with the information given you should be able to figure out something. Either that or read the entire article cited and quoted from on festivals.
- "Athens tracked 3 different calendars, the Prytany Calendar which divided the year into ten parts during which each tribe rotated chairing the Assembly, the Festival Calendar by which actual dates for sacrifices, etc. were scheduled and was very loosely related to the actual phases of the moon, and the actual lunar cycle known as Kata Selenes, or Kata Theon (according to Selene, or to the Gods). Kata Selenes produces a very irregular pattern of 29 and 30 day months. Any attempt to follow a regular pattern of 29 and 30 days will quickly fall out of synch with the moon."
Greek Months. It won't tell you everything, but with the information given you should be able to figure out something. Either that or read the entire article cited and quoted from on festivals.

Comments
That does not help me what so ever. Anybody know a sit that actually shows me the Athenian calender? Cuz thats what i actually need!
Hi,
The Festivals of Ancient Greece is a good link. Thanks for that.
Is there a more indepth explanation of the Athenian Calendar?
Thanks,
Maggie S
Ms. Gill, that is a terrible description of the Athenian calender, could you have at least have given a vague, even very vague, idea of when you think the months might fall? This site is all useless. I really thought it would be a bit better than wikipedia as you would have detailed well researched info but noooo. Forget this
Courageous – I think you just read the blog post, not the Greek months article, and probably not the article on festivals, either. The article on Greek months provides more details, although ultimately, it’s up to you to find out the lunar cycle and compare it with the summer solstice, as the article explains. I’m not sure I see how making guesses would show good research practices.