Today (Sunday, 7 April) is Palm Sunday, the last Sunday in Lent -- which marks the start of Holy Week in the Roman Catholic Church.

To commemorate the traditional occasion, Pope Paul celebrated Mass at St. Peter's Basilica, and also distributed palm and olive branches to Cardinals and Bishops. The rite recalls Jesus Christ's triumphal entrance to Jerusalem, when crowds laid down palm leaves and olive benches for His donkey to walk on.

Thousands of Roman Catholic faithful -- their crowds swelled by tourists of many other religions -- gathered in St. Peter's Square to celebrate Palm Sunday.