Beneath the Kapuzinerkirche, the Kaisergruft is the final resting place of most of the Habsburg royal family, including Empress Elisabeth. Opened in 1633, it was instigated by Empress Anna (1585–1618). Her body and that of her husband, Emperor Matthias (1557–1619), were the first entombed in this impressive vault. A total of 149 Habsburgs are buried here, including 12 emperors and 19 empresses.

English-language, 30-minute guided tours (included in admission) take place at 3.30pm Wednesday to Saturday.

Only three Habsburgs are notable through their absence here. The last emperor, Karl I, was buried in exile in Madeira, and Marie Antoinette (daughter of Maria Theresia) still lies in Paris. The third is Duc de Reichstadt, son of Napoleon’s second wife, Marie Louise, who was transferred to Paris as a publicity stunt by the Nazis in 1940.

The hearts and organs reside in Augustinerkirche and Stephansdom, respectively.