Quick bit of trivia from the field: it’s 43,560 because a Gunter’s chain is 66 ft and 10 square chains make an acre; that’s why old plats and 660x660 blocks pencil out to 10 acres on the map. Anyone else still getting deeds in chains/links and having to convert on the fly while laying out or drafting exhibits?
Yep - still see deeds in chains/links and convert on the fly. Handiest anchors: 1 chain = 66 ft, 1 link = 0.66 ft, and a half‑mile is 40 chains, so quarter‑quarter calls check fast; I keep a calc preset so 10 sq ch hits 43,560 without thinking.
Same here — I still get calls in chains/links, so I set my data collector to accept unit tags and just type 23.7 ch or 12 lk and let it auto-convert to feet, then sanity-check the 660x660 as 10 acres by dividing by 43,560 before staking. It’s saved me from a couple of fat‑finger blows on old plats, tbh.
Little hack: in Civil 3D I set a transparent alias so the distance field multiplies a ‘ch’ suffix by 66, so I can key 23.7ch and keep drawing in feet. Ever run into old ROW sheets where ‘chain’ meant 100 feet? I watch for stationing clues before trusting the units.