Adam Clarke on John 4:4

And he must needs go through Samaria - Or, It was necessary for him to pass through Samaria: for this plain reason, and no other, because it was the only proper road. Samaria lay northward of Judea, and between the great sea, Galilee, and Jordan; and there was therefore no going from Galilee to Jerusalem but through this province. See the note on Luk 17:11. From Jerusalem to Galilee through Samaria, according to Josephus, was three days' journey. See his own life.