522 BCE was the year of death of Polykrates, the tyrant of Samos, famous for having assembled a navy of hundred pentekontoroi, by that time the greatest navy of Greece. In Athens, Hippias had succeeded Peisistratos as the tyrant of Athens. In 522, Darius I gained kingship of Persia. He would create an empire comparable to the Imperium Romanum; an empire without bounds in space, focusing on people and defendable borders. Quite soon after the start of his reign, he entrusted Scylax of Caryanda to do the reconnaissance for his Indian aspirations:
There is a river, Indus, second of all rivers in the production of crocodiles. Darius, desiring to know where this Indus empties into the sea, sent ships manned by Scylax, a man of Caryanda, and others whose word he trusted.
Caryanda is a small island lying off the coast of ancient Caria. Nineteen kilometers to the south is Halicarnassus; the Dorian city of Artemisia, the famous naval commander. Forty kilometer to the north is Miletus which by the time of this story is a maritime empire with many colonies. The island, the town which lies on it, the bay [limnē] which forms its harbor [limēn], and Scylax himself; they all carry that same name: Caryanda.
Scylax started his journey by joining King Darius on his expedition towards Caspatyrus, a place in the Satrapy of Gandara. Herodotus mentions that this Satrapy belongs to the seventh, least profitable, tax district of the Achaemenid empire. For Darius and Scylax, Caspatyrus, which lies somewhere in the valleys of the Kabul River, was the door to a new world. From here they would be able to conquer the shores of the Indus River and explore the seas in which the Indus River empties.
For Herodotus, however, the land surrounding Caspatyrus was a desert, full of unknown and strange creatures. He shares a wonderful story in which the country gives room to a large type of ants [murmēx]; “not as big as dogs, but bigger than foxes. “These ants live underground, digging out the sand … and the sand which they carry from the holes is full of gold.”
The sand that contains gold is of such interest to the Indians, Herodotus tells us, that they “harness camels three apiece, males on either side… and a female in the middle: the man himself rides on the female, that when harnessed has been taken away from as young an offspring as may be.” The Indians ride after the gold in teams, “being careful to be engaged in taking it when the heat is greatest; for the ants are then out of sight underground.” (free after Herodotus 3.102.3–3.104.1) Herodotus goes on to explain:
So when the Indians come to the place with their sacks, they fill these with the sand and drive back as fast as possible; for the ants at once scent them out, the Persians say, and give chase. They say nothing is equal to them for speed, so that unless the Indians have a head start while the ants were gathering, not one of them would get away. They cut loose the male trace-camels, which are slower than the females; … the mares never tire, for they remember the young that they have left. Such is the tale. Most of the gold (say the Persians) is got in this way by the Indians. (Herodotus 3.105.1-105.2)
Meanwhile Scylax and his companions did not stay in Caspatyrus, but traveled from some 200 miles in easterly direction, following the downstream course of the Kabul River; a trickle of brown, muddy, water for most of the year. Close to the gorge where the Kabul River joins the Indus River, Scylax may have found a place to assemble or build his river ships.
He then followed the course of the Indus River, moving southward. He and his companions served as the reconnaissance team for the army of King Darius, who occupied the lands surrounding the Indus River and, around 516, Western India became the Achaemenid satrapy of Hinduš, referred to as “India” by the Greek writers. Further to the east, but in the same period, Siddhārtha Gautama, “Buddha”, attained enlightenment and began his ministry.
When Scylax finally reached one of the seven mouths of the river, he was in the place which nowadays is Karachi, a city with a population of 21 million people. Only one of the mouths, the one in the middle, was navigable; the others are shallow and marshy. By the shore was what later would be the market-town Krokola; the place where Alexander prepared for his travel back to Babylon.
The King turned around and traveled back to Persia, from where he would move across the Hellespont, into Thrace (513 BCE). The Ionian Sea-captain continued his journey, exploring the coastline from the delta of the Indus to the Persian Gulf. This voyage through the Erythraean Sea,  can be done best during the period of the North East monsoon; December–January.
The map in figure 3 depicts the routes of Nearchos (red line), which approximates the route of Scylax, and of Alexander the Great (green line). The people who lived on the sandy strip between the Ommanitic desert and the crystal clear ocean will later be described by Nearchos, as nomads and “fish-eaters” [ikhthuophagoi].
Much later, in the first century CE, this coast would have had small ports and market places that would host vessels underway from India to Arabia, shipping copper and sandalwood and timbers of teakwood and logs of blackwood and ebony, many pearls, clothing, wine, dates, gold and slaves.
Eventually Scylax may have reached Bandar Abbas, which during the reign of Darius already was a Persian settlement. Eventually, Darius’s commander, Silacus, would embark from Bandar Abbas to India and we may assume that it was a milestone for the ancient trade between Euphrates and Western India. Scylax, however, resumee his journey.
Firstly he crossed the Straits of Ormuz and then continued his voyage following the southwestern coastline of the Arabian peninsula. He passed by the barren coast in which Asikh, Moskha, and Cani may have been settlements, with roadsteads where ships could lie reasonably safe at anchor, of which the locals controlled the trade along the coast.
Finally Scylax arrived at the southwestern tip of ancient Yemen. Her main port was called Eudaemon (“Prosperous”), modern Aden. In Eudaemon all cargo from India and Egypt came together for transshipment, as nobody yet dared to sail from Egypt to India, or vice versa.
While staying close to the shore he may have passed through the eastern section of the sea strait which is named Bab-el-Mandeb; the Gate of Tears. This section of the strait is called Bab Iskender; Alexander’s Strait. The trade across the Bab-el Mandeb was controlled by the Sabaean kingdom, so this may have been the most dangerous part of his journey.
We do not know whether he followed the coast of Arabia or that of the Berber [barbaroi, barbarians] country, but gradually he moved north, in tremendous heat and against the prevailing winds, towards the Egyptian port of Mussel Harbor [Myos Hormos], located near the entrance of the Gulf of Suez. Strabo mentions that from this port sail around a 120 ships to Arabia and India. Here he may have ended his 30-month journey in which he covered the 3200 miles that separate the delta of the Indus River from the northern part of the Red Sea.
Following the exploration of Scylax, King Darius commanded a canal to be excavated, providing access firstly to the Bitter Lakes and from there through the 50 km long valley of the Wadi Tumilat towards Zagadis in the eastern Nile delta:
Baines and Málek (1984), p. 48.
This [the canal from the Nile to the Red Sea] was begun by Necho II [610 BCE – 595 BCE], and completed by Darius I, who set up stelae c. 490 [BCE], … and later restored by Ptolemy II Philadelphus, Trajan and Hadrian, and Amr ibn el-‘Asi, the Muslim conqueror of Egypt. Its length from Tell el-Maskhuta to Suez was about 85 km (52.82 mi). 
An inscription on one such stele says:
I commanded to dig this canal from the Nile…to the sea which goes from Persia; afterwards this canal [was dug] thus as I commanded, and [ships] passed from Egypt by this canal to Persia as was my [will].
Psammetichus left a son called Necos, who succeeded him upon the throne. This prince was the first to attempt the construction of the canal to the Red Sea—a work completed afterwards by Darius the Persian—the length of which is four days’ journey, and the width is such as to admit of two triremes being rowed along it abreast. The water is derived from the Nile, which the canal leaves a little above the city of Bubastis, near Patumus, the Arabian town, being continued thence until it joins the Red Sea
One of their kings tried to make a canal to it (for it would have been of no little advantage to them for the whole region to have become navigable; Sesostris is said to have been the first of the ancient kings to try), but he found that the sea was higher than the land. So he first, and Darius afterwards, stopped making the canal, lest the sea should mix with the river water and spoil it.
From his port of arrival Scylax may have traveled overland to the Persian garrison in Memphis, to report and document his findings. His work, the Periplous of Scylax, is referred to by Hecataeus of Miletus when he wrote about the “Indus Satrapies” of the Achaemenides  and by Strabo, who refers to Scylax as an ancient writer.
If Scylax returned to Greece, then, in 510 BCE, he would have found Hippias expelled by the people of Athens, supported by Cleomenes I, the King of Sparta. In the spring of 480 BCE Indian troops would march with Xerxes’s army across the Hellespont and fight for him in the Battle of Thermopylae. They became the first-ever force from India to fight on the continent of Europe.
 1. The estimate for the year of death of Polykrates (522) and the start of the reign of Darius are based upon Herodotus Histories 3.126.1 “After the death of Cambyses”
 Near present-day Bodrum, Turkey.
 “Miletus was first founded and fortified above the sea by Cretans, where the Miletus of olden times is now situated, being settled by Sarpedon, who brought colonists from the Cretan Miletus and named the city after that Miletus”. (Strabo, Geography 14.1.6)
 William Smith. 1854. Dictionary of Greek and Roman Geography. London. (entry on Miletus) “Owing to its excellent situation, and the convenience of four harbours, one of which was capacious enough to contain a fleet, Miletus soon rose to a great preponderance among the Ionian cities. It became the most powerful maritime and commercial place; its ships sailed to every part of the Mediterranean, and even into the Atlantic; but the Milesians turned their attention principally to the Euxine, on the coasts of which, as well as elsewhere, they founded upwards of 75 colonies. (Plin. Nat. 5.31; Senec. Cons. ad Helv. 6; Strab. xiv. p.635; Athen. 12.523.)” .
 John Burke (photo): Kabul River, Old Bridge, Bala Hissar in the distance. public domain, via Wikimedia Commons
 In a first century Greco-Roman periplus, the Periplus of the Erythraean Sea 10.39 “The ships lie at anchor at Barbaricum.” Schoff, Wilfred Harvey, ed. (1912). Casson, however, uses the Greek text: Períplous tē̂s Eruthrâs Thalássēs; the same place is called Barbarikón.
 Based on Herodotus Histories 4.44.
 Abraham Ortelius. 1592. Map, for the Periplus Maris Erythraei. Plate  from: Theatrum orbus terrarum / Abraham Ortelius. Antverpiae: Apud Ioannem Bapt. Vrintium, 1609. via Wikimedia Commons. https://commons.wikimedia.org/wiki/File:PeriplusAncientMap.jpg
 Vasileff (The Policy of Darius and Xerxes towards Thrace and Macedonia) notes that the Scythian campaign of Darius I was a military expedition into parts of European Scythia by Darius I, the king of the Achaemenid Empire, in 513 BCE
 Eruthra Thalassa, a Greek name, literally “Sea of Erythras”, involving the maritime area of the modern Persian Gulf, Arabian Sea, Indian Ocean and modern Red Sea. Compare Gildersleeve’s note to Pindar Pythian 4.20: “On their return from Kolchoi, the Argonauts passed by the Phasis into Okeanos, thence to the Red Sea, carried their ship overland twelve days, reached Lake Tritonis in Libya, and found an outlet from Lake Tritonis to the Mediterranean.” Compare Herodotus 1.180.1: “The city (Babylon) is divided into two parts; for it is cut in half by a river named Euphrates, a wide, deep, and swift river, flowing from Armenia and issuing into the Red Sea.“
 Note as discussed by Wilfred H. Schoff (1913): Erythrín thálassan more accurately is Sea of Erythras; Red Sea would be Thálassa Erythrà, in which Erythrà is the adjective. The former, Sea of Erythras, is more accurate, because the sea is not red, except in the rare case of Exodus 7.17-21, while Erythras may have been the name of an illustrious hero, a priest of this area, or a king “of the rosy morn“.
 Arrian: Anabasis Alexandri: Book VIII (Indica) Tr. E. Iliff Robson (1933): XXVI “…Below the Gadrosians, as you follow the actual coast, dwell the people called the Fish-eaters. The fleet (of Nearchus) sailed past their country.”
 The Greco-Roman periplus, the Períplous tē̂s Erythrâs Thalássēs mentions the settlements of Ommana and Oraea.
 Map titled Nearchos’s Voyage. S. Phalieros, Maios 1998 Chania, at display at in the Nautical Museum of Chania, Crete. Photo by Author.
 Herodotus 4.44 “…and voyaging over the sea west, they came in the thirtieth month to that place from which the Egyptian king sent the above-mentioned Phoenicians to sail around Libya.”
 Strabo: The Geography of Strabo: 2.5.12 “At any rate, when Gallus was prefect of Egypt, I accompanied him and ascended the Nile as far as Syene and the frontiers of Kingdom of Aksum (Ethiopia), and I learned that as many as one hundred and twenty vessels were sailing from Myos Hormos to India, whereas formerly, under the Ptolemies, only a very few ventured to undertake the voyage and to carry on traffic in Indian merchandise.”
 According to an Arabic legend, the Bab-el-Mandeb (Gate of Tears) derives its name from the numbers who were drowned by the earth quake which separated Asia and Africa. named for the numbers who were drowned) [“Bab-el-Mandeb” in Encyclopædia Britannica, Ninth Edition, Volume III]
 Berbers, or Barbaroi: “foreigners”; them speaking a tongue foreign to the ancient Greeks.
 Damer, Mrs. G.L. Dawson. “Diary of A Tour in Greece, Turkey, Egypt, and The Holy Land, Volume 2.” (Henry Colburn, London: 1841).
 Figure 4: Painting of Suez, 1841. Damer, Mrs. G.L. Dawson. “Diary of A Tour in Greece, Turkey, Egypt, and The Holy Land, Volume 2.” (Henry Colburn, London: 1841). p 128b. From Wikimedia Commons.
 John Baines & Málek, Jaromír, joint author (1980). Atlas of ancient Egypt. New York, N.Y Facts on File Publications
 Aristotle, Meteorology 1.14.Translated by E.W. Webster. http://classics.mit.edu/Aristotle/meteorology.1.i.html
 (Hec. fr. 179; F. H. G. i. 12) cited in How & Wells commentary on Herodotus 4.44.
Aristotle, Meteorology 1.14 E.W. Webster
Arrian Anabasis Alexandri. Translated by E. Iliff Robson. 1933. Online at Fordham University:
Bivar, A. D. H. 1988, “The Indus Lands”, in John Boardman; N. G. L. Hammond; D. M. Lewis; M. Ostwald (eds.), Cambridge Ancient History, Volume IV – Persia, Greece and the Western Mediterranean, c. 525 to 479 B.C. (Second ed.), Cambridge University Press, pp. 194–210.
Casson, Lionel, ed. 1989. The Periplus Maris Erythraei: Text With Introduction, Translation, and Commentary, Princeton: Princeton University Press.
Charlesworth, M. P. “Some Notes on the Periplus Maris Erythraei.” The Classical Quarterly, vol. 22, no. 2, 1928, pp. 92–100. JSTOR, www.jstor.org/stable/635595.
Gildersleeve, Notes, in: Pindar: The Olympian and Pythian Odes. Basil L. Gildersleeve. Anne Mahoney. edited for Perseus. New York. Harper and Brothers. 1885.
Online at Perseus
Herodotus, Histories 3.91, 3.102.2, 4.44, 6.89, 7.65. Herodotus, with an English translation by A. D. Godley. 1920. Cambridge. Harvard University Press.
Online at Perseus
How, W.W., Wells, J. A Commentary on Herodotus. On Perseus:
Online at Perseus
Períplous tē̂s Erythrâs Thalássēs. W.H. Schoff (tr. & ed.), The Periplus of the Erythraean Sea: Travel and Trade in the Indian Ocean by a Merchant of the First Century (London, Bombay & Calcutta 1912)
Pliny, and Healey, John F. 2004 Reprint edition. Natural History, a Selection. Penguin. London, New York.
Schoff, W.H. The Name of the Erythraean Sea, Source: Journal of the American Oriental Society, Vol. 33 (1913), pp. 349-362. Published by: American Oriental Society. Published by: American Oriental Society. Stable URL: https://www.jstor.org/stable/592840
Smith, William. 1854. Dictionary of Greek and Roman Geography. London.
Online at Perseus
Strabo, Geography 2.5.12, 14.1.6, 14.2.20. Translated by Horace Leonard Jones. 1917–1932. Harvard.
Vasileff, Miroslav. 2015. The Policy of Darius and Xerxes towards Thrace and Macedonia
Figure 1: John Burke (photo): Kabul River, Old Bridge, Bala Hissar in the distance. Public domain, via Wikimedia Commons
Figure 2: Abraham Ortelius. 1592. Map, for the Periplus Maris Erythraei. Plate  from: Theatrum orbus terrarum / Abraham Ortelius. Antverpiae: Apud Ioannem Bapt. Vrintium, 1609. Public domain, via Wikimedia Commons.
Figure 3: Map titled Nearchos’s Voyage. S. Phalieros, Maios 1998 Chania, at display at in the Nautical Museum of Chania, Crete. Photo by Author
Figure 4 Figure 4: Painting of Suez, 1841, 1841. Damer, Mrs. G.L. Dawson. “Diary of A Tour in Greece, Turkey, Egypt, and The Holy Land, Volume 2.” (Henry Colburn, London: 1841). p 128b.
Creative Commons Attribution-Share Alike 2.5 Generic license, via Wikimedia Commons.
Figure 5: annie brocolie (map): Canal of the Pharaohs, started under Pharaoh Sesostris’ I reign, c. 1960 BC but not completed until at least Darius I.
Creative Commons Attribution-Share Alike 2.5 Generic license. via Wikimedia Commons.
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