729. Forming a Caravan

Shabbos 16:12                      

Let’s say that someone spends Shabbos in a valley and he constructs a partition around his camp. If the enclosed area is no larger than needed to plant two seah of seed, he may carry throughout it. If the enclosure is larger than this, he may only carry within four cubits. The same is true when two people camp in such a valley but if three or more Jews spend Shabbos in this way, they are considered a caravan and they may carry as far as their needs may require - even several miles – so long as there is no space larger than needed to plant two seah left empty without utensils. If the enclosure includes a space larger than two seah that is empty, and therefore useless to them, they may only carry within four cubits. A child under bar mitzvah does not count when determining the members of a caravan (i.e., two adults and a child are not considered a caravan).

Shabbos 16:13                                                               

If three people enclose an area of sufficient size for their needs and make this their residence for Shabbos, they may continue carrying throughout the enclosure even if one of them dies on Shabbos. If two people enclose an area larger than needed to plant two seah as their Shabbos residence, they may only carry within four cubits even if a third person joins them on Shabbos. Everything is determined by the situation when they establish their Shabbos residence, not on the number of people who may be present over the course of Shabbos.