Chapter 4, Mishna 1
What happens when a person’s produce is taken outside his Shabbos boundary? Depends on whether it was taken out intentionally or unintentionally. If I don’t know where my Shabbos boundary is, I may count 2000 “medium” steps from my dwelling even though measuring usually prohibited on Shabbos, since it’s for the sake of the mitzvah. What if my Shabbos dwelling is in a valley and idolaters built a vast enclosure for residential purposes around the valley after Shabbos began? How far may I walk? How far may I carry? Shmuel and Rav Huna disagree. What if my Shabbos boundary ends in the midst of a city? May I walk further? May I carry further? Can I carry further than I can walk? If so, how?