Eupalinos Tunnel - The Third Wonder of Samos
April 11, 2008 Samos History No CommentsEupalinos the Tunnel Builder from Samos
The Eupalinos Tunnel in the south of the Greek island Samos,Greece, was built around 550 - 520 BC by the
Greek Architect Eupalinos of Megara,son of Naustrophos. Eupalinos or in the Greek way spelled ‘Eypalinos’ was one of three great men living at the same time on the same Greek island. One of them was the tyrant Policrates, who ruled Samos Island at the time and the third man here was Pythagoras of Samos, whom we all remember barely from our math lectures at school. This is, amongst many others, a strong indicator of how important Samos was around 550 BC.
A Man Needs a Plan
Eupalinos of of Megaras saw himself in front of quite a challenge and water was urgently needed since Samos doesn’t have any rainfall at all during summer time and the city was growing at a steady rate. To save time Eupalinos planned the tunnel to be started from both sides of the mountain and the two pipes would meet at half way. Working space was a problem; labor was not. There where enough slaves to be used. At the time of the construction, Samos was ruled by the famous tyrant Policrates and he himself had ordered the tunnel to be built. The estimated building time of the Eupalinos Tunnel ranges from five to fifteen years. Like most of Samos Island, the mountain they had to digg through is solid limestone and it was surly hard labor with very limited tools in a terrible closed space. Many of the slaves must have died in these tunnels.
The Greek Historian Herodotus (484 -425 BC) named the Eupalinos Tunnel “The Third Wonder of Samos Island”. In Histories 3.60 he states:
“And about the Samians I have spoken at greater length, because they have three works which are greater than any others that have been made by Hellenes: first a passage beginning from below and open at both ends, dug through a mountain not less than a hundred and fifty fathoms [200 m] in height; the length of the passage is seven furlongs and the height and breadth each eight feet, and throughout the whole of it another passage has been dug twenty cubits in depth and three feet in breadth, through which the water is conducted and comes by the pipes to the city, brought from an abundant spring: and the designer of this work was a Megarian, Eupalinos the son of Naustrophos.”
How to Build A Tunnel - 3′000 Years Ago
Two groups working under the direction of the architect and engineer Eupalinos of Megara dug the tunnel through Mount Castro to build an aqueduct for fresh water supply of the ancient capital of Samos, Tigani, today called Pythagoreion. The tunnel measures 1030 meters - 3432 feet - in length and it was tricky to make a plan.
Since two parallel lines never meet, Eupalinos recognized that a mistake of more than two meters horizontally (approximate cross section was 1.8 by 1.8 m), would make him miss the meeting point. Having calculated the expected position of the meeting point, he changed the direction of both tunnels, as shown in the picture (one to the left and the other to the right), so that a crossing point would be guaranteed, even if the tunnels were previously parallel and far away.

There was also the possibility of deviations in the vertical sense, even though his measurements were quite accurate with only four centimeters of vertical difference in the opening of the tunnels, Eupalinos could not take a chance. He increased the possibility of the two tunnels meeting each other, by increasing the height of both tunnels. In the north tunnel he kept the floor horizontal and increased the height of the roof, while in the south tunnel, he kept the roof horizontal and increased the height by changing the level of the floor. His precautions in the vertical sense proved unnecessary, since measurements show that there was practically no mistake.
Hide a Tunnel
Hiding the tunnel was of utmost defensive importance. The aqueduct ran underground and was not easily found by an enemy who could otherwise cut off the water supply of the city. And if it was found it was easy to defend within the hills. Tigani was in desperate need of fresh water supply, the city was inhabited by 300′000 people plus a steady flow of ships arriving empty and leaving Samos Harbor with full water tanks.
The Eupalinian Aqueduct has deployed fresh water to Tigani for over a thousand years, this is proven by archaeological findings. Nowadays the well on the north side has dried out and so has the Eupalinos tunnel. Today the tunnel is open to visitors for a small entrance fee. The tunnel has opening hours and is closed on Mondays.





As a young man, he left his native city for Croton, Calabria, in Southern Italy, to escape the tyrannical government of Polycrates. According to Iamblichus, Thales, impressed with his abilities, advised Pythagoras to head to Memphis in southern Egypt and study with the priests there who were renowned for their wisdom. He also was discipled in the temples of Tyre and Byblos in Phoenicia . It may have been in Egypt where he learned some geometric principles which eventually inspired his formulation of the Pythagorean Theorem that is now called by his name.
The Pythagoreans taught that the purpose of life was to purify the soul and body. They expanded on their Orphic beginnings to include “purification” through science and knowing. To reach purification they taught that one had to discover the “harmonies” of the cosmos - and scientific (mathematical) enquiry was the vehicle with which to find them.
A Fairy Tail on a Greek Island 

