Beethoven's funeral procession on 29 March 1827, was attended by an estimated 20,000 Viennese citizens. Franz Schubert, who died the following year and was buried next to Beethoven, was one of the torchbearers. Beethoven was buried in a dedicated grave in the Währing cemetery, north-west of Vienna, after a requiem mass at the church of the Holy Trinity (Dreifaltigkeitskirche). His remains were exhumed for study in 1862, and moved in 1888 to Vienna's Zentralfriedhof. In 2012, his crypt was checked to see if his teeth had been stolen during a series of grave robberies of other famous Viennese composers.

There is dispute about the cause of Beethoven's death: alcoholic cirrhosis, syphilis, infectious hepatitis, lead poisoning, sarcoidosis and Whipple's disease have all been proposed. Friends and visitors before and after his death clipped locks of his hair, some of which have been preserved and subjected to additional analysis, as have skull fragments removed during the 1862 exhumation. Some of these analyses have led to controversial assertions that Beethoven was accidentally poisoned to death by excessive doses of lead-based treatments administered under instruction from his doctor.

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