Although the Desert of Chartreuse

satisfied the spiritual needs of Bruno and his six companions - isolation, silence, solitude - the small community of monks had physical needs that could not be ignored.

Initially, a large area of the dense forest surrounding their tiny settlement was cleared and the space was used to grow crops and to graze a small herd of cattle that supplied the monks with milk, butter and cheese.

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Martinet

In addition to the iron-making during the 12th century

and following centuries, the rapid expansion of sailing fleets created a need for tall, straight trees to be made into ship's masts. The mountain forest was filled with tall, straight trees and the monks could harvest these for funds needed to maintain La Grande Chartreuse, the order's mother-house, and other Chartreuse monasteries springing up throughout the world.

Both iron making and ships' mast harvesting came to a halt when King Louis XV of France ordered a drastic reduction in the number of trees that could be cut down for industrial activities. With trees for charcoal limited, the Chartreuse blast furnaces were closed down and, without the iron, the "Martinets", where raw iron was tranformed into objects, were also closed.       
By the final days of the 18th Century, the monks were in dire economic straits : the iron making business was defunct, the trees in the mountains stood tall and straight but could not be harvested, and the anti-cleric attitude of the French Revolution compelled the Chartreuse Monks to leave their beloved Desert of Chartreuse and flee to Spain.

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