Jorn Utzon, an architect who designed one of the world’s most recognizable buildings  the Sydney Opera House  but never saw it finished, died in Copenhagen on Saturday. He was 90.

He died of heart failure in his sleep, according to his son Kim.

Mr. Utzon left Australia amid controversy seven years before the Opera House was completed. He lived out most of his final decades on the Spanish island of Majorca while his gull-roofed building came to symbolize Australia, 10,000 miles away.

As a young architect Mr. Utzon worked for Gunnar Asplund in Sweden and Alvar Aalto in Finland before establishing his own practice in Copenhagen in 1950. In 1956 he read about the Sydney Opera House competition in a Swedish architecture magazine. He spent six months designing a building with sail-like roofs, their geometry, he said, derived from the sections of an orange. Mr. Utzon’s plan was championed by Eero Saarinen, the Finnish architect who was one of the judges in the competition.

Image Jorn Utzon was the designer of the Sydney Opera House. Credit... Agence France-Presse

In 1957, Mr. Utzon  who until then was hardly known outside his native country  was declared the winner, and for the next five years he worked on the project from his office in Denmark. In 1962, he moved with his wife, Lis, sons Jan and Kim, and daughter, Lin, to Sydney.