Did I hear that right? A sar volume?

Yes, a sar volume.

Let me digress a little bit and I will get back to that.  We take agriculture for granted and don't worry too much about how much land it takes to feed us, but that has not always been the case.  In the poorer countries, about .17 hectare per person is under plow and in the richer countries, about .36 hectare per person.  A hectare is 10,000 square meters, so that is about 1,700 to 3,600 square meters per person.  Current yields are about 1,500 kilograms per hectare for rainfed crops and several times that for irrigated crops.

A sar is a square rod and a rod is 12 cubits or 6 meters in length, so a sar is 36 square meters.  The basic farm plot in Sumeria, named the "iku," just happens to be 100 sar, or 3600 square meters, just about exactly what we plant per person now.

Interestingly enough, the yield per iku on the Sumerian farms was just short of 1,000 kilograms per iku, actually coming in around 750 to 900 kilograms.   This would be about 7.5 to 9 kilograms per sar.  A liter of barley should weigh in at just about 640 grams.  Dividing the 750 - 900 kilograms by 100 to find out the yield per sar and then by .64 for the density of barley, this would be about 4.8 to 5.8 sila of barley per sar.

In the Code of Hammurabi, a boatman or a herdsman was paid 6 gur a year, and a farmer would make 8 gur.  A gur is about 300 sila, making the payment to the boatman and the herdsmen about 1,800 sila a year and the farmer about 2,400 sila.  If you divide 1,800 by 365, you get 4.9, 2,400 divided by 365 gives you 6.5.  This makes the sar look about like the area that the ancients considered would be necessary to feed a man for a day.

What makes this really interesting is that the sar is the basic unit of area and volume that is used to figure out the daily work quotas.  A sar volume of earth is that ninda square area counted a cubit high, or 18 cubic meters.  A worker is expected to dig a sar of earth in three days, make it into bricks in three days, or mix it thoroughly enough to make bricks in six days.

Carrying it a league is another story.  That would take 1 man quite a while a basket at a time.

This makes me wonder how they worked some of this stuff out.  At Çatalhöyük archaeologists found storage units that were sized to keep food for just about one winter season.