A sanitarium (also spelled sanatorium) is a special kind of hospital where people go to recover from long-term illnesses, especially diseases that affect the lungs like tuberculosis. Before modern antibiotics were invented, tuberculosis was a deadly disease that spread easily between people. Sanitariums were built in places with fresh mountain air and sunshine, far from crowded cities, because doctors believed this environment helped patients heal.

Patients at sanitariums often stayed for months or even years, resting outdoors on porches even in cold weather, eating nutritious meals, and gradually regaining their strength. These institutions were most common from the late 1800s through the 1940s. Many sanitariums were beautiful buildings set in peaceful locations, designed to feel calm and restorative.

Though we rarely build new sanitariums today since antibiotics can cure tuberculosis, some of the old buildings still stand as reminders of how people once fought serious illnesses. The word sometimes appears in historical novels or movies set in the early 1900s, when sanitariums were an important part of medical care.