A group of former Swiss Vatican Guards, who arrived in Rome after re-enacting a historic march from Switzerland undertaken 500 years ago, will receive a special papal blessings today, reported Swissinfo.org.

Their arrival in Rome launched the 500th-anniversary celebrations that mark the founding of the "smallest army in the world."

On January 21, 1506, 150 Swiss mercenaries marched to Rome in response to an invitation from Pope Julius II, who sought his own private army for protection against the Church’s enemies.

This past month, about 70 former guardsmen, from 25 to 76 years of age, took 28 days to march the same 720-km route from Bellinzona, Switzerland to Vatican City, following the historic "Via Francigena" pilgrimage route to Rome. Fifty other former papal guards walked part of the way.

The former Swiss guards will be officially welcomed by a delegation of officials from Rome and the Vatican. They will receive a blessing from Pope Benedict XVI today.

On Friday, Swiss President Moritz Leuenberger is scheduled to give a welcome speech on behalf of the Swiss government during an official ceremony in the Vatican City. New Swiss guardsmen will be sworn in on Saturday in St Peter's Square.

A wreath will also be laid in memory of the Swiss guards who died in 1527 defending the Vatican against the forces of Charles V.

Today, some 110 papal guards are responsible for the security of the Vatican as well as the person of the Pope.