Called "one of the greatest engineering achievements of ancient times," it is a tunnel 1,036 meters (4,000 ft) long, "excavated through Mount Kastro on the Greek island of Samos, in the 6th century BCE" during the reign of Polycrates.
Other Byzantine writers opposing Christian mortalism were John the Deacon, Niketas Stethatos, Philip Monotropos (Dioptra pp. 210, 220), and Michael Glykas.