Albert Barnes Commentary Jeremiah 52:7

"Then a breach was made in the city, and all the men of war fled, and went forth out of the city by night by the way of the gate between the two walls, which was by the king`s garden; (now the Chaldeans were against the city round about;) and they went toward the Arabah." — Jeremiah 52:7 (ASV)

Broken up ... the plain - Or, “broken into ... the Arabah” (Deuteronomy 1:1).