In 1962 the CIB building at the northern corner of the site was demolished and the park was extended to occupy the entire square, with a total area of . A new layout for the gardens was prepared as a joint state and local government scheme in preparation for the visit of Queen Elizabeth II to Brisbane in March 1963. Brisbane City Council landscape architect, horticulturalist and author, Harry Oakman, was responsible for the design and landscaping, and architectural detailing was undertaken by Department of Works architect Graham De Gruchy.