From the early 9th century to the 1789 Revolution, wars and invasions
succeeded one another in Picardy so that the local populations had
to protect themselves and could find no better hideouts than Naours
caves, which they used at regular intervals.
Every time they had to flee in the face of the enemy, the refugees
settled down there for an indefinite period : they packed up and
went down there, along with their livestock and ploughing implements,
that is their most treasured possessions. Family groups of different
sizes were accommodated accordingly, in one chamber, or in an
area or along galleries on either side of which the well laid-out
cells, depending on their dimensions, could shelter between 4
and 12 people altogether.