How is a valley measured for the techum — does the rule differ depending on whether the plumb line diverges 4 cubits?
Synopsis
For a valley where the plumb line diverges 4 cubits: if the span fits 50 cubits, use havla'ah; otherwise use 4-cubit kidor. If the valley is deeper than 2,000 cubits, measure the entire slope. If the plumb line does not diverge 4 cubits: span if possible; if not, measure only the flat bottom, even if deeper than 2,000 cubits.
More in Cooking on Yom Tov
What type and length of rope must be used when measuring the Shabbos limit (techum)?
4 opinions
How does the measurer handle a river that interrupts the measurement of the Shabbos techum?
3 opinions
At what height on the body must each person hold the measuring rope, and how tightly must it be stretched?
3 opinions
Must the techum always be measured directly opposite the city, even when terrain obstacles make measurement difficult?
2 opinions
How is a steep hill (one whose plumb line does not diverge 4 cubits at the base) treated during techum measurement?
3 opinions
How is a moderately steep hill (rising 10 handbreadths in 5 cubits) measured for the techum?
3 opinions across 3 eras
When a hill that rises 10 handbreadths in 4 cubits cannot be spanned in 50 cubits, may it be measured by estimation alone (omdan) or must the 4-cubit rope kidor method be used?
2 opinions
What is the reason a valley deeper than 2,000 cubits requires measurement of the entire slope even when the plumb line diverges?
2 opinions
Related from other topics
How does the wording of the Al HaEtz blessing differ based on whether the fruit grew in Israel or outside Israel?
Al HaMichyah
If there is doubt whether an item was brought from outside the techum, what is the ruling?
Using Vessels on Shabbat
If there is doubt whether flutes or items were brought from outside the techum, what is the presumption?
Using Vessels on Shabbat
When three courtyards open into one another and the middle placed its eruv in each outer courtyard separately (in two different houses), versus placing both outer courtyards' eruvin in one house in the middle courtyard — does this affect whether the outer courtyards are permitted with each other?
When Eruv Members Violate Shabbat
What is the minimum required amount of food for a valid shituf, and how is it measured for different food types (relish vs. non-relish, liquids)?
Calculating Eruv Techumin
What are the carrying rules for a courtyard that opens into two alleyways, depending on whether it made a shituf with one, both, or neither alleyway?
Calculating Eruv Techumin
Discussion
Discussion coming soon.
The Daily Law
One question. Every opinion. Every morning.
A new halakhic question and the full spectrum of rabbinic thought, delivered daily.