The 1955 Sydney Opera House design competition received 233 entries. The number is associated with the international competition that ultimately selected Danish architect Jørn Utzon’s design.
The competition brief sought a major hall seating about 3,000 people and a smaller hall for about 1,200. Entries came from architects around the world, and the jury included figures such as Eero Saarinen, Leslie Martin, and New South Wales government architect Cobden Parkes.
Utzon’s proposal was initially placed among the rejected designs before Saarinen reportedly asked for it to be reconsidered. The jury announced Utzon as the winner on 29 January 1957. His concept was still far from a finished building: the roof geometry, construction methods, interiors, and performance spaces would require years of redesign and engineering work.