The original hospital structure was destroyed on October 18 , 1935 , when a major earthquake struck Helena . The current historic main hospital building was built in 1937 – 1939 to replace it . This structure is a T-shaped , two-story , concrete building with a basement . The Helena office of J. G. Link & Company were the architects of this Art Deco/Early Moderne design , which includes a flat roof , colored concrete , and diamond-shaped tiles . The south side has a central entrance . There are many bays and windows around the exterior of the building . The interior floorplan has remained essentially the same as it was in 1939 . The hospital became the county-owned convalescent home on September 24 , 1961 and was renamed the Cooney Convalescent Home . Dr. Cooney , in whose honor the hospital was renamed and the street was named , began working there in the 1920s and served as administrator until the 1950s . In 1984 , the Cooney Convalescent Home moved to a new location on the other side of Helena , near St. Peter 's Hospital , and the building was converted to office space , mostly occupied by various healthcare practitioners
major earthquake struck Helena
1935 Helena earthquake
Lewis and Clark County Hospital Historic District