The school is situated on of landscaped grounds only from the
Adelaide central business district on Hackney Road and North Terrace in the suburb Hackney. Neighbouring suburbs College Park and St Peters were named after the school. The main campus' facilities include seven ovals, a hockey pitch, ten tennis courts and two swimming pools. It features mostly heritage architecture, such as "Palm House" (built for
William Peacock), but also includes modern buildings. The "Big School Room" is thought to be Australia's oldest classroom still in constant use. The most recent addition to the school has been the extensive redevelopment and extension of the Pentreath Building, featuring new technological state-of-the-art classrooms and wide open corridors with learning in mind. After redevelopment, it became the centre of the Middle Years program, which sees Year 7s and 8s moving into the Senior School as regular students. The next most recent redevelopment is the Junior School, featuring new classrooms and lecture facilities as well as an observatory. In the Senior School, the Burchnall Sports Centre is also a recent development, which includes two basketball courts, a 25-metre pool, a diving pool, a strength and conditioning room, and café. The school is soon to commence construction of the 'Leadership and Ethics Centre' featuring lecture facilities, a new Year 12 common room and the school's museum. The college also owns a large outdoor education property in Finniss, situated on several hectares of land on the banks of the
River Finniss. The property includes dormitories, teacher accommodation and a gymnasium, and students are involved with the property's revegetation program of native flora. The property's location on the banks of the
River Finniss makes it an ideal location for the school's Rowing and Sailing camps. A significant source of the school's revenue is the estate of
Benjamin Mendes da Costa. Da Costa, a successful Adelaide businessman, died in 1868 and bequeathed to the school an estate of £20,000 (over £2,200,000 in 2020
GBP). The bequest was subject to the
life interests of ten relations; the last surviving relation died in 1910 and in 1912 the property was vested in the school. A large portion of the estate remains land in prominent city-centre locations. Income generated by the estate is used to subsidise the fees of all students, along with several scholarships and bursaries. The College sold one of its properties, Da Costa Arcade, near
Rundle Mall, in 2005. A somewhat common Adelaidean
urban myth asserts that the Da Costa estate was intended to be given to the
Catholic church rather than the Anglican, and that the funds were awarded to Saints after a supposed legal battle. This myth has no basis in fact and most probably stems from misconceptions of da Costa's religion due to
his Portuguese family name. == Extracurricular activities ==