Before revision: As the Cambridge Ancient History: Persia, Greece and the Western Mediterranean C. 525 to 479 B. C. states , this evidently was as far eastwards as Darius intended to go, at least for the time being.
After revision: As A. Fol and N. G. L. Hammond state , this evidently was as far eastwards as Darius intended to go, at least for the time being.