The Austrian Museum of Architecture in Vienna says Johannes Spalt died Saturday, three days after his birthday, according to the Associated Press.

Spalt, whose death was announced Monday, was considered one of the greatest postwar Austrian architects. While still at university, he cofounded the now famous “arbeitsgruppe 4” which shaped the architectural landscape in Austria’s rural regions with churches and other public buildings that promoted the modern approach in traditional landscapes.

Spalt was rector at the Vienna’s University for Applied Arts and was awarded the order of merit of Vienna and other prizes for his outstanding contribution to the field of architecture.