Measuring time in Ancient Athens

Calendars

Calendars are complicated things. They have to take into account the actual movements of the sun, moon and stars, as well as the perceived dictates of religious systems. 

In ancient Greece, they differed from city state to city state all over the Hellenic world. For instance, in Athens the year began in mid-summer. In other parts of the Hellenic world it began mid-winter. 

Leo von Klenze's vision of the Akropolis of Athens around 430 BC

There seem to have been, in fact, three separate ways of measuring the passing of the year in Athens in the mid-5th century BC: 

1)    the political or civil calendar (which dictated the meetings and change-overs of the Council of 500)

2)    the festival calendar (which dictated when festivals and gods' birthdays were to be held)

3)    the agricultural calendar (based on the seasons and such agricultural practises as planting, harvesting, and pruning).

Months

The months listed below are those used for the festival calendar in Athens around the time of Themis’ story in The Boy with Two Heads. The correlation between the ancient and the modern months should not be taken as exact.

Summer

Hekatombaion                  July/August

Metageitnion                    August/September

Boedromion                      September/October

Autumn

Pyanepsion                        October/November

Maimakterion                   November/December

Poseideon                          December/January

Winter

Gamelion                           January/February

Anthesterion                      February/March

Elaphebolion                     March/April

Spring

Munichion                         April/May

Thargelion                         May/June

Skirophorion                      June/July

Most of the months are named after a festival (sometimes no longer celebrated) or the god of a festival held during that month.

Days

Each month had either 29 or 30 days. These were numbered in three sets of ten days according to the phases of the moon. The first ten days seem to have gone from 1 to 10 ‘waxing’, the second ten days from 11 to 20 ‘full’, but the last ten counted down from 10 to 1 ‘waning’.

Years

Years were given names, not numbers. They had the name of one of the magistrates that served for that year – the 'eponimous archon'. There seem to have been four-year cycles between Grand Panathenaia festivals (during our early August).  The four year intervals between Olympic Games were later named after the winner of the sprint at the Games, but at the time of The Boy with Two Heads this had not yet become the norm.

From the frieze of the Parthenon in Athens showing cavalry horses  as it is now 
and as it would have been painted when it was new.
It shows the Grand Panathenaia procession and runs round all four sides of the temple.

The above facts are from a Wikipedia article that I have cross-referenced with many, more complex accounts. The whole article is clear and easy to understand and you can find it here. I used it (among other sources) to keep track of the passing year in ancient Athens as I wrote The Boy with Two Heads.

November 5th, 2015
A much more comprehensive article was published today by Christopher Planeaux on his blog at www.ancient.eu/article/833/.