Christopher Columbus died in 1506 from Reiter's Syndrome, an illness caused by intestinal bacterial infections or sexually transmitted diseases like gonorrhea. No one is sure how old Columbus was at the time of his death, but historians place his age at around 55.
When Columbus returned from his travels to Spain in 1503, he was beginning to feel ill. He was suffering from inflammation of the eyes as well as arthritis, and doubts were raised about his mental condition. By May of 1505, his condition was dramatically worsening. He died on May 20, 1506.
As of 2014, Columbus is buried in Spain at the Seville Cathedral.