Strabo Geography 11.8.9

[9] Eratosthenes gives the distances as follows: From Mt. Caspius to the Cyrus River, about one thousand eight hundred stadia; thence to the Caspian Gates, five thousand six hundred; then to Alexandreia in the country of the Arians, six thousand four hundred; then to the city Bactra, also called Zariaspa, three thousand eight hundred and seventy; then to the Iaxartes River, to which Alexander came, about five thousand; a distance all told of twenty-two thousand six hundred and seventy stadia. He gives also the distance from the Caspian Gates to India as follows: To Hecatompylus, one thousand nine hundred and sixty stadia; to Alexandreia in the country of the Arians, four thousand five hundred and thirty; then to Prophthasia in Drangge, one thousand six hundred (others say one thousand five hundred); then to the city Arachoti, four thousand one hundred and twenty; then to Ortospana, to the junction of the three roads leading from Bactra, two thousand; then to the borders of India, one thousand; a distance all told of fifteen thousand three hundred stadia. ¹ We must conceive of the length of India, reckoned from the Indus River to the eastern sea, as continuous with this distance in a straight line. So much for the Sacae.