The Kapuziner Church (just inside the ring behind the Opera) has housed the Imperial Crypt, the burial vault of the Habsburgs, for some 3 centuries. Capuchin friars guard the final resting place of 12 emperors, 17 empresses, and dozens of archdukes. Only their bodies are here: Their hearts are in urns in the Loreto Chapel of the Augustinerkirche in the Hofburg complex, and their entrails are similarly enshrined in a crypt below St. Stephan's Cathedral.
Most outstanding of the imperial tombs is the double sarcophagus of Maria Theresa and her consort, Francis Stephen (François, duke of Lorraine, or, in German, Franz von Lothringen, 1708-65), the parents of Marie Antoinette. The "King of Rome," the ill-fated son of Napoleon and Marie-Louise of Austria, was buried here in a bronze coffin after his death at age 21. (Hitler managed to anger both the Austrians and the French by having the remains of Napoleon's son transferred to Paris in 1940.)
Emperor Franz Joseph was interred here in 1916. He was a frail old man who outlived his time and died just before the final collapse of his empire. His wife, Empress Elisabeth, was also buried here after her assassination in Geneva in 1898, as was their son, Archduke Rudolf, who died at Mayerling.