It always astonishes me that such hordes can lie undiscovered in farm fields. How could it not be hit by a plow in 1,000 years? How could it not be pushed to the surface by the action of the earth in such a long time?
Frost heave pushes rocks and boulders to the surface of farm fields every year and farmers have to clear them. We’ve got some farm fields near us with astonishing windrows of boulders that must be 6 feet high and 10 feet wide at the base. Of course, this is glacial moraine area, so there are LOTS of rocks. But the action is the same.
My brother-in-law was from Honduras and his family's business was growing sugar cane.
Many years ago when plowing the fields, they would occasionally unearth caches (for lack of a proper word) of buried Mayan stone carvings, usually broken by the plows.
However, he was able to salvage one intact and bring it home to the states.