I can't think of any examples where they'd show up in aerial photos, but the traces of original Spanish land grants in California are still clearly in the land registry, some still undivided.

A section isn't large for a farming operation. It's only a square mile or 640 acres. Drive through the Central Valley of California and you'll pass through many much larger parcels. My husband and I own a section not far from Yosemite (as the crow flies). It's pretty rugged and remote - basically wilderness with a house and some cattle.