From the wars of Sihon and Og to modern-day Eilat, the southern borders of Eretz Yisrael remain a halachic and historical mystery. Rav Shlomo Katz takes us deep into the confusion around Nachal Mitzrayim, the shifting number of nations to conquer, and the conflicting maps passed down through Torah and tradition. What does all this mean for the mitzvah of yishuv ha’aretz today? Are places like Be’er Sheva and the Negev still part of the command? With passion and clarity, we uncover how the lines we draw shape the Torah we live.