Eruv Techumin
Question
According to what do we measure the 2000-amah Shabbos boundary? Is it based on the actual distance a person walks, or on the aerial (straight-line) distance, or something else? And from where do I measure it — from the apartment I am in, or from the last house of the city until I reach the place I need to go (such as the synagogue)?
Answer
Shalom uVracha,
a. The distance is measured as the straight-line (aerial) distance.
b. It is measured from the last house of the town.
One must be familiar with the layout of the area, since sometimes the houses are considered part of the same city, while in other cases they are regarded as separate from the city and therefore not included in the measurement.