Apart from Herodotus admiring comment on Samians and the aqueduct (Link), other ancient sources are silent about Eupalinos’ feat. In any case, archaeological research revealed that the tunnel remained in use for more than a thousand years, and was restored in Roman times using reinforcing wall built with small stones and plaster, forming a barrel-vaulted roof. Actually, in the Roman era another surface aqueduct was constructed to carry water to Pythagoreion. In the Byzantine times the tunnel was used as a shelter and a sanctuary and a makeshift cistern that collected groundwater was built near its centre. Since after the 7^th c. AD it was abandoned, and forgotten.

Due to Herodotus’ comment, many travellers searched for the tunnel in modern times. In 1853, the French archaeologist Victor Guérin searched for the “great spring” of Herodotus locating Agiades and excavating part of the northern end of the subterranean conduit. However, it was the monk Kyrillos Moninas from the nearby Agia Triada monastery that discovered some years later the northern entrance of the tunnel.

In 1882, the first attempts to clean and restore the water channel to working order were abandoned due to the great difficulties arising. The water was brought to ‘Tigani’ (Pythagoreion previous name) through an external, surface conduit. A small building was erected on the southern entrance of the tunnel, still on site.

In 1883, E. Fabricius, an archaeologist of the German Archaeological Institute in Athens (DAI), visited the island and surveyed the tunnel up to the point that could be visited at the time. He published a systematic description and a sketch on an British Admiralty Map, rendering the aqueduct known to researchers and the wide public.

In 1884, the archaeologist E. Stamatiadis published the article «Περί του εν Σάμω ορύγματος του Ευπαλίνου», commenting on the discovery. Topographical measurements was taken almost 75 years later by W. Kastenbein, however in 1971 U. Jantzen (1909-2000), Director of the DAI, succeeded after long preparations to excavate and research the tunnel (1971-1973). After that H. Kienast undertook the laborious project of documentation and publication, concluded 20 years later. The site was opened to the public in the 1980’s.