Swiss Guards celebrate 515 years in 2021.

The Vatican will hold its annual ceremony to swear-in new recruits into the Swiss Guards, the world's smallest army, on Thursday 6 May.

The pomp-filled event, held in the S. Damaso courtyard of the Apostolic Palace, will see the 34 new guards take a solemn oath of allegiance to the pope.

It will be the second year in a row that the ceremony will take place without an audience, in line with covid-19 protocols.

Traditionally held each year on 6 May, last year's event was postponed until October, due to the coronavirus emergency.

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A handful of family members will attend this year's ceremony which will be streamed live via the Swiss Guards website from 17.00.

The annual event commemorates 6 May 1527, when 147 Swiss Guards died protecting Pope Clement VII from the army of the Holy Roman Emperor.

The pope fled via the 800-m Passetto di Borgo passageway to the nearby refuge of Castel S. Angelo.

The 135 current Swiss Guards belong to the world's oldest standing army which celebrated its 515th anniversary in January this year.

• Visiting Castel S. Angelo, Rome's Castle

The guards must be male and of Swiss nationality, as well as being Catholic, unmarried and aged between 19 and 30.

They must also have undergone intensive Swiss military training and be a minimum height of 174 cm.

In addition to protecting the pope, the army performs ceremonial duties and assists at Vatican functions, and is famous for its ancient halberd weapons and its blue, gold and red uniform.

Led by Commander Christoph Graf, the soldiers serve for between two and 25 years at the Vatican, in the service of the pope.