Mount de Sales is located on of land, from which one can see the
Inner Harbor and the Baltimore city skyline. The back yard of the school is home to a garden featuring a statue of the
Blessed Virgin Mary. The campus also includes the Center for Performing Arts and Student life (opened in 2021), athletic fields, a convent, and a gymnasium. Most classes are still held in the original school building, begun in 1852 and expanded in the 1860s. The main building, which is listed on the
National Register of Historic Places, retains architectural traces of the cloistered sisters of the
Visitation Order who founded the school. The chapel, located in the center of the main building, is the oldest place of worship still in use in Baltimore. The stained glass windows in the chapel, original to the building, were cast in the same place and manufacturing technique as the famous stained glass of the
Cathedral of Chartres,
France. The windows are located at the back of the building, as Catholics in the area were undergoing much persecution at the time of the building's planning, and its founders wished to avoid vandalism and protest. Over the years, the chapel has had several pipe organs. The current instrument was built by George Jardine & Son in 1884. This historic pipe organ was played in recital during the Organ Historical Society Convention in July 2024. The building also includes the Music Hall, which has details such as
trompe-l'œil painting and is where graduation is held annually, the
Padre Pio library, which contains relics of that saint and a mosaic in his honor, computer labs, a spacious art studio, the Ramona Carrigan Science Center, research lab, and newly added STEM and robotics rooms. The Regina Keenan Knott Alumnae Hall was formerly an infirmary for the school's boarding students. At one time it was connected to the main building by a walkway which has since been demolished. The building's front is the opposite of the main building so that visitors would not see any of the sick or otherwise ailing girls. The building now houses the school's development and alumnae relations groups. The Constance and Samuel Pistorio Sports Complex was dedicated in 1999. Its design was modeled after the architecture of the campus' historic buildings. The facility is located across from the main building, on a piazza featuring gardens and a bronze statue of
Saint Joseph the Worker. The St. Cecilia Center, a 24,000-square foot building that opened in 2021, features music and dance classrooms, practice rooms for student performers, fully equipped scene shop and storage space for technical theatre students, 400-seat fixed lower-level orchestral section, 200-moveable seat upper-level multi-use space, and control room for audio, lighting, and visual equipment. ==Brother School==