Study Eruvin folio 56B with parallel Hebrew-English text, traditional commentary, and modern study tools. Free access to Babylonian Talmud online.
A baraita states: One who squares a city in order to determine its Shabbat limit renders it like a square tablet, and then he also squares the Shabbat boundaries and renders them like a square tablet. Consequently, after squaring the city, he adds additional squares of 2,000 cubits to each of its s
And when he measures the Shabbat limit, he should not measure the 2,000 cubits diagonally from the middle of each corner of the city, because if he were to do so, he would lose the corners, i.e., the limit would extend only 2,000 cubits on the diagonal from each of the corners. Rather, he measures
As a result, it will be found that the city gains 400 cubits in this corner and another 400 cubits in the opposite corner. Assuming that the city itself is round and has a diameter of 2,000 cubits, as will be explained below, when the borders of the city are squared, approximately 400 cubits are add
Abaye said: And you find this projection of the additions to the city’s borders and Shabbat boundaries to be correct in the case of a round city that is 2,000 cubits by 2,000 cubits.
The Talmud cites a similar discussion with regard to the Levite cities, the 48 cities given to the Levites in Eretz Yisrael instead of a tribal inheritance. It was taught in a baraita that R' Eliezer, son of R' Yosei, said: The boundary of the cities of the Levites extends 2,000 cubits in each direc