The Diolkos is a paved road which was used for the transport of boats by land on a platform ("puller of boats").
Its western section was excavated to a length of 255m. on the Peloponnesos side of the Isthmus and of 204 m. on the Sterea Hellas side, in the precinct of the School of Engineering.
Its width is 3,40 - 6,00m. It is paved with square blocks of poros and carried two grooves in the middle, at a distance of 1,50 m. from each other. On its western side it ended on a paved quay.
It became necessary to built the "diolkos" in order to provide a quick passage for the boats between the Saronic Gulf and the Corinthian Bay. It was constructed during the 6th century B.C., probably during the tyranny of Periandros in Corinth. Its western end was reconstructed at the beginning of the 4th century B.C. It was used for the transport of small boats, mostly warships, up to the 9th century A.D. as is confirmed by various sources.
Source: odysseus.culture.gr