Designed to house 250 souls

The Trans-Allegheny Lunatic Asylum was constructed between 1858 and 1881 and remains the largest hand-cut stone masonry building in North America. Some sources claim it is the second largest of its kind in the world, behind only the Kremlin. Designed by architect Richard Andrews, the asylum was based on the Kirkbride Plan, a 19th-century model for mental health facilities that emphasized fresh air, natural light, and the therapeutic power of environment. Its long, staggered wings were carefully laid out to ensure that each room had access to sunlight and cross-ventilation.

Although the building was large, it was originally intended to house around 250 patients. This limit reflected the belief that a superintendent could only manage a certain number of individuals effectively while maintaining quality of care. The hospital opened to patients in 1864, but as years passed and funding models changed, the patient population ballooned. By the 1950s, the asylum held more than 2,400 people in overcrowded, often inhumane conditions.

The facility finally closed in 1994 after years of decline and shifting attitudes toward mental health treatment. Its closure had a significant economic impact on the local community, and the effects of that loss are still felt today.

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