Engineer (6th century BC)

Eupalinos was an engineer from Megara, best known for his monumental engineering achievement, the Eupalinian aqueduct, a 1 km tunnel dug through a mountain.

During the 6th century BC, the tyrant of Samos Polycrates requested the construction of an underground aqueduct that would supply water to his city. The tunnel would have to be underground in order to prevent any possible siege from pirates while also providing possible retreat to citizens. This meant that the tunnel had to cross a total distance of 1 km under a 250 meter mountain. Polycrates hired the only engineer he considered capable of constructing it, Eupalinos.

To achieve this difficult task, Eupalinos used the necessary geometric solutions to figure out the tunnel’s route and angle. What is astounding for its time, is that the tunnel was simultaneously excavated from both ends of mount Castro (amphistomon), meeting at the middle.  He used trigonometry to measure the distances around the mountain and calculated the exact course of the tunnel from both ends. Eupalinos then charted the tunnel’s route on top of the mountain in order to keep track of its construction underground.

The construction was done using simply picks, chisels and hammers. The tunnel’s height and width were 1,80 m and 1,80 m respectively (5.9 ft).  To avoid subsidence, he added curves rock plaques on the ceiling that formed an arch. To measure the distances, the workers wrote the decadic numerals of the Greek alphabet every 10 fathoms. He also built a small 70 cm trench where pipes were placed to carry the water to the city. The pipe channel extended outside the tunnel from both ends, covering a total distance of 2,5 km. He gave it a small inclination  in order for the water to flow constantly.

The tunnel was completed between 550 and 530 BC and came to be known as Eupalinian aqueduct. It took a total of 10 years and 4000 workers to complete. Proud of his achievement, Eupalinos wrote the word ”ΠΑΡΑΔΕΓΜΑ” inside the tunnel, which means ”example” or ”model”. Ultimately, it covered a distance of 1 km under the 250 meter mount Castro. It was used extensively to carry water to the city of Samos for 1100 years, until it was abandoned during the Byzantine era.

Today it stands in the exact same way it was designed and constructed. It stands as a marvel of human engineering and Eupalinos is considered one of the greatest engineers in human history.


  1. “Eupalinos”. Helios New Encyclopaedic Dictionary. Passas, I. Athens, 1946. Print.
  2. NIKitas Mikas. ”Τα μαθηματικά υδρεύουν τη Σάμο”. Online posting. Youtube, 9 Mar. 2013. Web. 30 Jun. 2017.
  3. Πηλεύς Ορέστης. ”Ευπαλινειον Όρυγμα στη Σάμο The Eupalinos Tunnel Samos”. Online posting. Youtube, 1 Jun. 2010. Web. 30 Jun. 2017.



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s