Adjacent to the Montrose House (1850) on the original property site purchased by the School Sisters of Notre Dame, one of the first buildings, "Gibbons Hall", was constructed in an "L-shaped" structure. It surmounted by its landmark white wooden tower, and opened in 1873 and became the landmark site symbolizing "Notre Dame of Maryland," which offered instruction to girls and young women. Gibbons Hall was named for the then incumbent Archbishop of Baltimore and second American Cardinal of the Church, James Gibbons.