For nearly 180 years, papal conclaves have chosen a new pope in three to five days. In centuries past, they've taken a lot longer.

Cardinals have no contact with the outside world after the master of liturgical ceremonies utters the words “Extra Omnes” the Latin phrase for “all out,” to ask all those present except the cardinal electors to leave the Sistine Chapel to begin the voting process.

Cardinals will gather for the papal conclave — the centuries-old tradition through which a new head of the Catholic Church is elected — starting on May 7.