Saint Peter was an important figure in the early Christian Church. He was the first apostle to be ordained by Jesus, and it seems that he was the leader of the twelve apostles. Around the age of 60, between the years 64 and 68 AD, he was crucified in the Neronian Gardens, by the order of the Emperor Nero. Origen (in Eusebius, Church History II.1) says: "Peter was crucified at Rome with his head downwards, as he himself had desired to suffer." Peter had stated that he wanted to be crucified upside down so as not to imitate, and thereby disrespect, his mentor, Jesus. The Neronian Gardens encompassed the present site of the Piazza San Pietro and the area to the left of the 16th century basilica of St. Peter's in Rome, ironically now one of the holiest places for the Roman Catholic Church. Peter's remains have been moved several times since his death, but what are believed to be his bones and other relics related to him are now kept in a crypt below the floor of St. Peter’s Basilica. Since the fourth century, the vault, with the altar built above it, has been the most highly venerated martyr's shrine in the West.