Smoke as a means of announcing the results of the votes in the conclaves held in the Vatican has its roots in the year 1878. Formerly, for centuries, the opening of a single window signaled that a new Pope had been elected. However, the signaling changed starting in 1878, when the conclaves moved from the Quirinal Palace to the Sistine Chapel.
Regarding the duration of the conclaves, there was a particularly notable occasion in history: one lasted for three years, from 1268 to 1270, according to a report published by the RFI site. This exceptional prolongation marks one of the longest periods in the history of the conclaves.
