Hosszú sábeszi séta városban (techum)

[From the above,] it follows that a person may walk throughout the expanse of [any] city, even if it is as large as Nineveh, whether or not it is surrounded by a wall.
Similarly, it is permitted for a person to walk two thousand cubits in all directions outside the city. [When calculating these two thousand cubits, the entire area] is considered to be square, like a tablet, so that [the area in between] its furthest corners will also be included.
If a person goes beyond two thousand cubits up to a distance of twelve mil, he should be given "stripes for rebelliousness". If he goes even one cubit beyond twelve mil, he should be punished by lashing [as prescribed] by the Torah.

Come and hear another difficulty from the following baraita: If one established his Shabbat residence through his physical presence in a city, even if it is as large as Antioch, or in a cave, even if it is particularly large, like the Cave of Zedekiah, king of Judah, he may walk through all of it and another two thousand cubits beyond it. The baraita teaches the case of a city that is similar to that of a cave: Just as a cave is presumably desolate, i.e., uninhabited, so too the city must be one that is desolate. And only in the case where he established his Shabbat residence through his physical presence would yes, this halakha apply; but if he merely placed his eiruv there, no, he may not measure his two thousand cubits from the edge of the city.

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