The Babylonians had many festivals and feasts. Probably the most important of these was the New Year's Festival. The festival happened in the first eleven days of the month Nisan which meant that the festival coincided with the spring equinox. This is because the equinox marks the beginning of another cycle when the days get longer and then shorter again until the winter equinox. The days shorter, and then longer, and then the year ends when day and night are the same length, the spring equinox.
On the first five days of the New Year's Festival there were many ceremonies of purification. These culminated when on the fifth day the King was taken, by the High Priest, to Marduk in the Temple of Esagila. The King had his insignia removed and he was then accused of crimes against the city of Babylon. The King was hit and then was forced to kneel and plead his innocence. The King then had his insignia restored.
On the sixth day the statue of Nabu was taken from his temple in Borsippa, about ten miles from Babylon, and brought to his father's, Marduk's temple in Babylon.
The tenth day was the great climax to the celebration. Marduk, Nabu and many other gods assembled and went, by river and road, to a place called the Akitu house. Here a ceremonial battle took place showing Marduk overcoming the forces of evil. The gods then returned to the temple of Esagila.