Tunnel of Eupalinus

Efpalinus Tunnel

Useful Information

Location: North of the town Pythagoreon, Island of Samos.
Fee: Adults EUR 4.
Classification: ExplainWater Supply
Light: electric.
Dimension: L=1,350m.
Guided tours:  
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535 BC water tunnel constructed by the architect Eupalinus.
7th cty BC aqueduct abandoned.
1882 rediscovered by the monk Cyrillus Monina.
1971-1973 tunnel cleaned out and studied by German archaeologists.


A highlight of Samos is the Tunnel of Eupalinus, an adit built in the 6th century BC under the reign of the tyrant Polycrates. Samos enjoyed its greatest prosperity in history during the 6th century, under his reign. He built four extraordinary structures, which are the most important sights of the island until today:

  1. the Polycratean walls, the 7km long walls of the city Samos
  2. the Tunnel of Eupalinus, part of the water supply of the ancient city
  3. the harbour mole, the oldest manmade port of the Mediterranean
  4. the temple of Hera, with her sanctuary, Heraion

The Tunnel of Eupalinus is one of the so-called Eight Wonders of the ancient world, to be exact it is the eighth wonder. Together with MiscHezekiah's Tunnel in Jerusalem, Israel, it is considered the peak of pre-Classical water engineering technology.

"I have talked so much about the Samians, because, of all the Greeks, they have made the three greatest works of construction. One is a double-mouthed channel driven underground through a hill nine hundred feet high. ... The second is a mole in the sea around the harbor, one hundred a twenty feet deep. The length of the mole is a quarter of a mile. The third work of the Samians is the greatest temple that I have ever seen."

There is a "tunnel nearly a mile long, eight feet wide and eight feet high, driven clean through the base of a hill nine hundred feet in height. The whole length of it carries a second cutting thirty feet deep and three broad, along which water from an abundant source is led through pipes into the town. This was the work of a Megarian named Eupalinus, son of Naustrophus."


The Tunnel of Eupalinus is on average 1.80m wide by 1.80m high, 1,350m long and and crosses Mt Ambelos 180 meters below its summit. All in all 7,000 cubic meters of rock had to be removed to build it. It is the central part of an aqueduct, which brought drinking water to the ancient city of Samos.

The tunnel was dug simultaneously from both ends, two teams of labourers, five men working at the rockface at any one time, took ten years to complete it. While the tunnel is extremely well done, with straight walls and a level flor, cut through solid rock with simple and unsufficient tools, the true challenge is still a bit of a mystery. How did Eupalinus manage to meet so exact in the middle. Supposedly Eupalinus both correctly applied his geometric calculations and laid the line out correctly on the ground. This work has made Eupalinus famous.

The upper tunnel is mostly for maintenance of the water pipes, which are located in a second tunnel just below. The pipes were made of ceramics.