The Sword of Saint Peter the Rock Jesus Christ's Disciple

The blade was made from a single piece of iron with an added small cross-guard.

Total length: 70.2-centimetre (27.6 in), it was probably 1-centimetre (0.4 in) or 2-centimetre (0.8 in) longer, but the tip of the sword was destroyed by corrosion

Maximal width, at the tip: 9.4-centimetre (3.7 in)

There is a hole 10.3-centimetre (4.1 in) from the end of the hilt, which is 0.4-centimetre (0.2 in) in diameter

For many years, historians treated the sword as a copy, probably made in the 10th century, but research by scientists from the Polish Army Museum in Warsaw suggests that the weapon could have been made in the 1st century in the eastern borderlands of the Roman Empire.

The sword is mentioned for the first time in the 1609 Vitae Episcoporum Posnaniensium of Jan Długosz as being the original Roman sword (Gladius) used by Saint Peter in the Gospels, or a direct copy made for Pope Stephen VII. However, at this time Stephen was already dead, and the current pope was John XIII.

The sword arrived in Poznań in 968 as a gift from John XIII for either Bishop Jordan or Duke Mieszko I. The Archdeacon of Poznań Cathedral in 1699 writes about the sword, describing it as a part of St. Peter's sword brought to Poznań by Bishop Jordan, where it is usually kept in the cathedral treasury, except for the few times a year when it is shown to the people. The 1721 Decree of Poznań Cathedral Chapter refers to having the sword moved to the chapter house as a more proper placement for this noble artifact.

Source: en.wikipedia.org/wiki/Sword_of_Saint_Peter