Map of the European Scythian campaign of Darius I, about 513 BCE

"So the Scythians went searching for their enemies through the parts of their own country where there was forage for the horses and water, supposing that they, too, were heading for such places in their flight; but the Persians kept to their own former tracks, and so with much trouble they found the crossing. But as they arrived at night and found the bridge broken, they were in great alarm lest the Ionians had abandoned them.

There was an Egyptian with Darius whose voice was the loudest in the world; Darius had this man stand on the bank of the Ister and call to Histiaeus the Milesian. This the Egyptian did; Histiaeus heard and answered the first shout, and sent all the ships to ferry the army over, and repaired the bridge.

Thus the Persians escaped. The Scythians sought the Persians, but missed them again. Their judgment of the Ionians is that if they are regarded as free men they are the basest and most craven in the world; but if they are reckoned as slaves, none love their masters more, or desire less to escape. Thus have the Scythians taunted the Ionians.

Darius marched through Thrace to Sestos on the Chersonesus; from there, he crossed over with his ships to Asia."

-Herodotus, The Histories, Book 4.140-143

Map of the European Scythian campaign of Darius I, about 513 BCE.

Source:

https://commons.wikimedia.org/wiki/File:DariusScythes_fr.svg

Quote:

https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Herodotus/4F*.html