The fate of the World Youth Day is once more in question with the sudden announcement on Monday of the resignation of Pope Benedict XVI. His surprise move comes just months before the Rio de Janeiro in Brazil hosts on July 23 to 28 the religious pilgrimage usually held every three years.

The pope made the announcement of Rio de Janeiro's selection as host city in 2011 at the closing of the International World Youth Day in Madrid, Spain. The next one should have be in 2014 based on the usual three-year gap, but Vatican decided to make change so the Catholic event would not coincide with the FIFA World Cup which will also be held in Brazil in 2014.

History is apparently repeating itself in the Church losing a pope just months before a major international WYD celebration.

In 2005, four months to the WYD, to be hosted then by Cologne, Germany, Pope John Paul II died in April, leaving the WYD festivity organisers worried that the next pope might not continue the initiative made by the much-love and charismatic Polish pope in 1985.

Pope Benedict, however, carried the tradition and presided over two more WYDs hosted by Sydney, Australia in 2008 and Madrid, Spain in 2011.

Five months away from the Rio WYD, organisers of WYD and pre-WYD events are again groping in the dark what will happen next.

If the next pope decides to end the event, there would have been a total of 12 international WYDs held since 1985 which always draw record crowds for the papal mass. Here are the top five in terms of crowd attendance and their respective theme songs:

1. January 1995 - Manila, Philippines (5 million)

Tell the World of His Love

2. August 2000 - Vatican City, Rome (2 million)

Emmanuel

3. August 2011 - Madrid, Spain (1.4 to 2 million)

Firmes en la Fe

4. & 5. August 2005 - Cologne, Germany and August 1997 - Paris, France (1.2 million each).

Venimus Adorara Eum Hymn (2005)

Maitre et Signeur (1997)