The roof of St. Stephen's Cathedral in Vienna is made of what material?

The roof of St. Stephen’s Cathedral in Vienna is made of glazed tiles.

The cathedral’s steep, richly patterned roof is one of Vienna’s most recognisable landmarks. It is approximately 111 metres long and covered with about 230,000 individually coloured glazed tiles, whose reflective surfaces create the roof’s vivid geometric appearance.

The tiles are arranged into large heraldic and decorative designs. Above the choir, they form a double-headed eagle associated with the Habsburg monarchy; other sections display the arms of Vienna and the Republic of Austria. The roof is therefore both a protective covering and a monumental civic symbol.

The roof’s construction history also explains a common misconception. A fire in 1945 destroyed its wooden framework during the final stages of the Second World War. When the roof was rebuilt, engineers used more than 600 metric tons of steel bracing rather than recreating the original timber structure. That internal reinforcement does not change the roof’s visible material: its exterior remains a glazed-tile covering, not glass, copper, or slate.