The Tag der Deutschen Einheit (“Day of German Unity”) is celebrated each year as a public holiday on 3rd October. In 1990 it replaced the previous holidays of 17th June in West Germany and 7th October in East Germany.
The main celebrations are held in the capital city of a different state each year.
The date was chosen arbitrarily and celebrates the day in 1990 when re-unification took place. Celebrating the day the Berlin Wall fell was felt inappropriate, as by co-incidence it is also the anniversary of the Reichspogromnacht in 1938.
To hear a simple explanation in German, listen to the podcast:
(Press the “play” button to listen to the podcast)