College of Immaculate Conception, c. 1915.

The College of Immaculate Conception was a preparatory school and seminary established by Bishop Charles E. McDonnell in 1914 in the Fort Greene neighborhood of Brooklyn. In the first year of the program, a class of 110 young men met in the vestry of Saint John's Chapel. Construction broke ground for their own school at 555 Washington Avenue in December of 1914.

The program consists of a four-year high school program followed by a two-year college program. Students who wished to continue the priestly vocation were then assigned to a major seminary, where they would study for an additional six years. The program moved to a new Elmhurst campus in 1963.