660 feet is a furlong, which comes from one furrow length. It’s the distance two oxen can pull a plow (creating a furrow), without stopping to rest. Then the oxen and person standing atop the plow could have a little rest before turning around to plow the next furrow. Not sure how many furrows but if you repeat this process all day, you’ll have plowed an acre. Potatoes did not exist to farmers when this land measurement was in use. But 66 x 660 is the original definition of an acre, and the only reasonable explanation for why we have 43,560

In California we measure water in Acre Feet. I guess if you know how many acres you have, and how many inches of water your crops need, I guess you’ll know how many acre feet you need.