The bad old days – finding hoards without a metal detector
This is how hoards were found in the bad old days, before metal detectors. Smashed to pieces by the plough! Illustration from the book Coins of the Romans Relating to Britain By John Y. Akerman, Published 1836 (the book is reproduced in full at the link).
When archaeologists uncover hoards they are usually in the foundations of buildings. The classic example being hoards of Roman bronze coins (sometimes very large hoards) being uncovered in the foundations of Roman Villas and other structures. The Romans buried coin hoards in the foundations of buildings as offerings to the gods or household spirits.