 It is certified by The Joint Commission, employs more than 1,000 trained healthcare workers, and has a medical staff of approximately 300 physicians representing more than 40 specialties.Beginning as the Corona Community Hospital in 1933, the hospital has changed and expanded to meet the needs of the rapidly growing communities of Corona, Norco and Eastvale.In 1992, Corona Community Hospital merged with Circle City Medical Center, and the resulting entity became Corona Regional Medical Center.