Albert Barnes Commentary 1 Samuel 30:1

"And it came to pass, when David and his men were come to Ziklag on the third day, that the Amalekites had made a raid upon the South, and upon Ziklag, and had smitten Ziklag, and burned it with fire," — 1 Samuel 30:1 (ASV)

On the third day - This indicates that Aphek was a three-day march from Ziklag, a distance of about 50 miles, which agrees very well with the probable location of Aphek (1 Samuel 4:1). From Ziklag to Shunem would be no less than 80 or 90 miles.

In retaliation for David’s raids (1 Samuel 27:8–9), the Amalekites invaded “the south” of Judah (Joshua 15:21). However, because all the men were absent with David, there was no resistance. Consequently, the women and children were carried off as prey but were left uninjured.