John Gill Commentary Deuteronomy 3:1

"Then we turned, and went up the way to Bashan: and Og the king of Bashan came out against us, he and all his people, unto battle at Edrei." — Deuteronomy 3:1 (ASV)

Then we turned and went up the way to Bashan
Which seems to have been higher than the kingdom of Sihon: this was a fine country for pasturage, for the breeding of cattle, larger and lesser, and was famous for its oaks: it is the same country which in Josephus and others goes by the name of Batanea:

and Og the king of Bashan came out against us ;
got his forces together, and came out from Ashteroth, the royal city where he dwelt:

he and all his people, to battle at Edrei ;
another city in his kingdom, about six miles from the former; see (Deuteronomy 1:4) (Numbers 21:33) .