Sacred Heart-Griffin High School, often abbreviated SHG, is Springfield, Illinois' largest private high school. The school is Roman Catholic and is located in the Roman Catholic Diocese of Springfield in Illinois. It opened in the fall of 1987 after Sacred Heart Academy, an all-girls Catholic high school merged with Griffin High School, an all-boys Catholic High School located across the street. Even prior to the merger, certain classes at both schools were taught on a co-educational basis. The part of campus which formerly housed Griffin High School is now known as the West Campus. The part of campus which was home to Sacred Heart Academy is known as the East Campus. Both facilities are used by SHG, with most of the school's athletic facilities being located on the West Campus and the majority of the academic facilities being located on the East Campus.