Ask the Rov: I want to take a Shabbos stroll in the countryside. What do I need to know?
By Rabbi Chaim Hillel Raskin – Rov of Anash in Petach Tikvah
On Shabbos, one may not leave the city’s boundaries (techum Shabbos). Many rishonim hold that the prohibition is min haTorah, derived from the posuk, “each man mustn’t leave his place,” and it applies to walking a distance of 12 mil (12,000 amos) beyond a city. According to all opinions, miderabonon, one may not walk anything more than 2,000 amos (3149 feet) outside the city.1
From what point are the 2,000 amos measured?
If when Shabbos begins, one is situated in an open area outside of a city—e.g., on the highway—then we start counting after a virtual box of 8 amos—4 amos in each direction—is drawn around him. If one is in a house or fenced area outside of the city, the count begins from the surrounding fence or wall. (An exception to this is if the fenced-in area is larger than 133 sq. feet (beis sasayim) and it wasn’t gated for dwelling purposes—e.g., a large parking lot or farm.)
If one is situated inside a city, we start counting 2000 amos from the city’s boundaries. This applies even if there is no fence around the city, since the entire city is considered one dwelling place.2
Where does a “city” end?
The city ends when no more houses are near each other with a space of 70 amos and four tefachim (111 feet) of unenclosed area. Much attention must be given to rural areas where such spaces are common. (If there are two groups of three houses each, they can connect if there are less than 141 amos between them.)
When measuring a city, we first square the city to the due directions, before adding 70 amos and four tefachim of the city border and the 2000 amos.3 For a larger city, the square can substantially add to the size of the city, since the city line will be past the house that jots out the furthest. As these measurements are extremely complex and include many considerations, each location should be assessed by a rov proficient in these halachos.
The Gemara speaks of a river dock used by the residents and considered part of the city, despite not having an enclosure. Poskim raise the possibility that this would apply to all outdoor areas that are used by the residents for strolling — such as sidewalks or playgrounds — unlike roads that are used for travel.4 In practice, one should consult a rov.
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From The Weekly Farbrengen by Merkaz Anash