San Andreas, CA…Mark Twain Medical Center is a major provider of health care services and a major source of jobs for area residents. Founded in 1951, Mark Twain Medical Center is a 25-bed, critical access hospital providing inpatient acute care, outpatient services and emergency services; including three Specialty Care Centers and five community Medical Centers. Our Medical Staff represents a broad range of specialties that ensure access to high quality medical care in a rural community.