[12] RCCS was renamed Istanbul International Community School in 1979 to reflect that it was now open to all expatriate students.

The primary building at the Hisar Campus, known as the White House, was originally built for an English merchant family in the early 20th century.

The 2048 m2 wooded campus overlooks the Rumelian Castle (Turkish: Rumeli Hisarı) in the city's Sarıyer district and serves students from preschool to grade 3.

Facilities include a library, PE and music room, rubberized basketball court, football pitch, climbing wall, and two playgrounds.

[6][13] The school's primary, purpose-built campus is located 25 miles (40 km) west of the city center in Karaağaç, Büyükçekmece.

The 16 hectare (40 acre) campus which opened in 1999[12] caters to approximately 75% of the student body[11] and is home to 30+ classrooms and a separate Early Years building.

[6] An "automated library/media center, music rooms with practice studios, a purpose-built art atelier, a theater and outside amphitheater...2 gymnasiums, outside basketball/tennis courts, and a regulation-sized sports pitch" are available for use.