A Holy Door () is traditionally an entrance portal located within the Papal major basilicas in Rome. The doors are normally sealed by mortar and cement from the inside so that they cannot be opened. They are ceremoniously opened during Jubilee years designated by the Pope, for pilgrims who enter through those doors may piously gain the plenary indulgences attached with the Jubilee year celebrations. In October 2015, Pope Francis expanded the tradition by having each Roman Catholic diocese throughout the world designate one or more local Holy Doors during the Extraordinary Jubilee of Mercy, so that Catholics could gain the plenary indulgences granted during the Jubilee year without having to travel to Rome. History Pope Boniface VIII began the tradition of the Holy Year, known as a Jubilee, in 1300 and the Catholic Church has celebrated them every 25 years or so ever since. A major part of the Holy Year for Catholics is a pilgrimage to Rome and the ritual passing over the threshold of the holy door to symbolise the passing into the presence of God. At the same time, remission of the temporal punishment for the pilgrims' sins is granted, known as an indulgence. One of the earliest accounts of the Holy Year dates back to a Spanish historian, traveler and pilgrim called Pedro Tafur in 1437. Tafur connects the Jubilee indulgence with the right of sanctuary for those who had escaped persecution. He also noted its existence in pagan times for all who crossed the threshold of the Puerta Tarpea previously upon the site of the Archbasilica of St. John Lateran. Accordingly, at the request of Emperor Constantine I, Pope Sylvester I published a Papal Bull proclaiming the same immunity from punishment for Christian sinners who took sanctuary there. The privilege, however, was quickly abused and at some point was even commercialised resulting in popes consequently ordering the door to be sealed with a wall, only to be unsealed during Jubilee years. The wall was destroyed and the door opened once in a hundred years. This was later reduced to fifty years and now "opened at the will of the Pope". In 1450, the Florentine merchant Giovanni Rucellai of Viterbo cites that the first Jubilee door was opened in 1423 under the pontificate of Pope Martin V. Rucellai, who lived at the time also speaks of the five doors of the Lateran basilica: Pope Alexander