The building had three levels at the concourse, or Swanston Street, end, and four at the lower Elizabeth Street, or platform, end. Numerous shops and lettable spaces were provided, some on the concourse, but especially along the Flinders Street frontage, many at lower than street level, accessed by stairs, which created a fifth/basement level. The top three levels of the main building contain a large number of rooms, particularly along the Flinders Street frontage, mostly intended for railway use, but also many as lettable spaces. Numerous ticket windows were located at each entry, with services, such as a restaurant, country booking office, lost luggage office and visitors help booth, at the concourse or platform level. Much of the top floor was purpose-built for the then new Victorian Railway Institute, including a library, gym and a lecture hall, later used as a ballroom. Those rooms have been largely abandoned and decaying since the 1980s. For a number of years in the 1930s and 1940s, the building featured a creche next to the main dome on the top floor, with an open-air playground on an adjoining roof. Since 1910, the basement store beside the main entrance has been occupied by a hat store, known as 'City Hatters' since 1933.