As legend says, this is the day when Archimedes discovered the principal of displacement, which was done inside a bath. To celebrate his achievement, we take the time to run a bath and recognise the incredible learning potential of a bath. If not an educational experience, it sure is a fun time!
The date of this day is meant to be the exact day on which the displacement principal was discovered. This was calculated using some pretty precise astronomy calculations. In 2016, the Registrar at National Day Calendar proclaimed the day to be observed on June 14th, annually.