Tunnel of Eupalinos

The Eupalinos Tunnel  is considered as one of the most important engineering achievements of antiquity. It's a 1036 m long tunnel in Samos Island, Greece, built in the 6th century BC to serve as an aqueduct and therefore supply fresh water from Agiades spring the city of Samos (Pythagoreion). The Eupalinos Tunnel is an engineering feat of outstanding importance since it was the first time in the history of mankind that anyone had ventured to undertake a project of that magnitude with no similar reference. The Engineer Eupalinos built a tunnel under a mountain by starting to dig, simultaneously, from two portals diametrically opposite. All applied measurements using maths and geometry are of outstanding precision. Moreover, all evidence indicate that Eupalinos was ready to apply a solution for every difficulty that arose, due to unfavorable ground conditions that were partly encountered, as well as that he had the courage to bring his highly difficult project to a successful end. Eupalinos worked as a modern engineer 2500 year ago.