Herodotus offers a description of a canal that was dug by the Persian king Xerxes. There is archaeological evidence. The story is translated by translated by Aubrey de Sélincourt.
Xerxes' canal across the Athos
[7.22] On the previous occasion, it will be remembered,note[Mardonius' ill fated expedition of 492.] the Persian fleet came to grief in the attempt to round Mount Athos. In view of this, work had been going on here for the past three years or so [483-480] to prevent a repetition of the disaster. A fleet of triremes lay at Elaeus in the Chersonese, and from this base men of the various nations of which the army was composed were sent over in shifts to Athos, where they were put to the work of cutting a canal under the lash. The natives of Athos were also forced to help dig. Bubares the son of Megabazus and Artachaees the son of Artaeus were the Persian officers in charge.
Everyone knows Mount Athos - that lofty promontory running far out into the sea. People live on it, and where the high land ends on the landward side it forms a sort of isthmus with a neck of about a mile and a half wide, all of which is level, except for a few low hills, right across from the coast by Acanthus to the other side near Torone. On this isthmus to the north of the high ground stands the Greek town of Sane, and south of it, on Athos itself, are Dium, Olophyxus, Acrothoon, Thyssus and Cleonae - the inhabitants of which Xerxes now proposed to make islanders.
 I will now describe how the canal was cut. A line was drawn across the isthmus from Sane and the ground divided into sections for the men of the various nationalities to work on. When the trench reached a certain depth, the laborers at the bottom carried on with the digging and passed the soil up to others above them, who stood on ladders and passed in on to another lot, still higher up, until it reached the men at the top, who carried it away and dumped it. Most of the men engaged in the work made the cutting the same width at the top as it was intended to be at the bottom, with the inevitable result that the sides kept falling in, and so doubled their labor. Indeed they all made this mistake except the Phoenicians, who in this - as in all practical matters - gave a signal example of their skill. They, in the section allotted to them, took out a trench double the width prescribed for the actual finished canal, and by digging at a slope gradually contracted it as they got further down, until at the bottom their section was the same width as the rest. In a meadow near by the workmen had their meeting place and market, and grain ready ground was brought over in great quantity from Asia.
 Thinking it over I cannot but conclude that it was mere ostentation that made Xerxes have the canal dug - he wanted to show his power and to leave something to be remembered by. There would have been no difficulty at all in getting the ships hauled across the isthmus on land; yet he ordered the construction of a channel for the sea broad enough for two ships to be rowed abreast. [....]
 It was while Xerxes was here [at the canal] that Artachaees fell sick and died. He was a man of the Achaemenid family, much respected by Xerxes, and had been in charge of the construction of the canal. He was the biggest man in Persia - about 2.15 meters high - and had the loudest voice in the world, so that Xerxes was greatly distressed at his death and had him carried out and buried with all pomp and ceremony. The whole army helped to raise a mound over his grave.
The following is the text of an article by Yudhijit Bhattacharjee that appeared in the New York Times (November 13, 2001).
Persian Canal Discovery Is Testament to Ancient Engineering Skills
In 480 B.C., King Xerxes of Persia ordered his men to build a canal a mile and a quarter long through a peninsula in northern Greece - conceivably one of the biggest engineering assignments of its time.
The canal was critical to Xerxes' plan of invading Greece, a goal that his general, Mardonius, had unsuccessfully attempted 12 years earlier. Mardonius' fleet was destroyed in a storm while sailing around the tip of the peninsula, and Xerxes wanted to avoid a similar setback by building the canal.
Xerxes went on to invade Greece, starting a brief period of Persian conquest in Europe. In the 2,500 years since, historians have debated whether the famed Canal of Xerxes was really dug all the way from coast to coast. Some have doubted its existence, pointing to a rocky plateau that they argue would have made the construction an impossible task for workers of that day.
Now, scientists from Britain and Greece have come up with what they say is conclusive evidence that the canal was indeed built. Using geological information gathered from several yards below the earth's surface, where the structure now lies buried, the scientists have drawn a map detailing the canal's dimensions and course. The findings confirm the description given in an account by the ancient Greek historian Herodotus, which some scholars have long regarded with skepticism.
Buried under centuries of silt and alluvium, the structure is testament to remarkable military strategy, work-force management and civil engineering. It also tells of shortsightedness and haste, and of a king who was probably in such a hurry to conquer that he never thought of preserving the canal as a permanent waterway.
"From the analysis of sediments in the canal, we know that it probably had a short lifetime," said Dr. Richard Jones, the lead researcher on the project and an archaeologist at the University of Glasgow. "The Persians did not think of it as a monument that would remain for centuries. Once their ships were through, that was the end."
Spanning about 100 feet at the surface, the canal was just wide enough for two war galleys to pass. Its sides sloped inward, forming a width of roughly 50 feet at the bottom, about 45 feet below the surface.
"It was a colossal enterprise," said Dr. Ben Isserlin, an archaeologist at the University of Leeds who started the canal exploration project in the early 1990s. "There were no pulleys. So the workers had to shovel earth into baskets and pass them along, from one person to the next, all the way to the top."
The mapping of the canal was a laborious enterprise itself. Dr. Jones and his colleagues used a seismic method that has traditionally been used in oil and mineral prospecting. Essentially, they hit a piece of metal placed on the ground with a heavy hammer, sending shock waves into the earth. By analyzing the time it took the waves to travel back up, the scientists were able to draw a seismic profile - a kind of phantom image - of the buried waterway.
"This was too big a target for conventional archaeological techniques," said Dr. Vassilis K. Karastathis, a member of the team that conducted the seismic survey and a geophysicist at the National Observatory of Athens in Greece. The team's findings were reported in The Journal of Applied Geophysics.
The canal structure imaged by the geophysical team was confirmed by analyzing sediment samples drilled from different depths.
Dr. Maria Brosius, a scholar of ancient history at the University of Newcastle Upon Tyne, said the engineering skills showcased by the canal had been around before Xerxes. "The ability to build a structure like that can be traced to Babylonian and Assyrian roots," she said.
Canal building, Dr. Brosius said, may even have been known in the kingdom of Urartu, which existed between the ninth and sixth centuries B.C. extending over part of what is now Armenia.
The construction was as much a feat of management as of engineering. Xerxes is believed to have drafted Phoenician engineers and to have assigned teams of workers to different sectors of the canal.
Upon completion of the canal, the Persian fleet made it safely to the Aegean Sea, where it was joined by the troops that had taken the land route from the north. The ships sailed on to Greece. Xerxes' soldiers stormed the coast and advanced deep into Greek territory.
They destroyed Athens but eventually lost to the Athenians in a battle that ended the Persians' fleeting imperial presence in Europe.
"The canal was forgotten," said Dr. Jones, the lead researcher.
- B.S.J. Isserlin et al., "The Canal of Xerxes on the Mount Athos Peninsula" in Annual of the British School at Athens 89 (1994) 277-284
- Dietrich Müller, Topographischer Bildkommentar zu den Historien Herodotos', 1987 Tübingen)