Eureka!

According to Wikipedia: "Eureka" comes from the Ancient Greek word εὕρηκα heúrēka, meaning "I have found (it)"

Archimedes

The exclamation 'Eureka!' is famously attributed to the ancient Greek scholar Archimedes. He reportedly proclaimed "Eureka! Eureka!" after he had stepped into a bath and noticed that the water level rose, whereupon he suddenly understood that the volume of water displaced must be equal to the volume of the part of his body he had submerged. He is said to have been so eager to share his discovery that he leapt out of his bathtub and ran through the streets of Syracuse naked...

Eureka District

Many a story is told as to how Eureka got its name. The favourites are:

* In 1875 when the Piako Swamp was busy being drained/reclaimed, a group of people were having lunch on a hill. Someone asked the name of the place where the picnic was being held and having then found out it was unnamed, the suggestion was made that Eureka sounded a good name as it was the initials of all the first names of the ladies present.

* The company in charge of organising the vast network of drains to help transform the swamp into useable agricultural land was looking for a high spot for their headquarters. When Captain William Steele found a hill he exclaimed "Eureka, I have found it!"