Several relics in Christendom have been claimed as the Holy Lance of Longinus — the spear-head of the Roman centurion who pierced Christ's side at the crucifixion. The four principal candidates are at Rome (St. Peter's), Vienna (the Imperial Treasury), Echmiadzin in Armenia, and Antioch (later disappeared).
The Vienna lance — most documented in its history — was already venerated in the time of Charlemagne and was carried into battle by Otto I against the Hungarians at the Battle of Lechfeld in 955. It contains a nail-shaped iron core which 14th-century inscriptions identify as 'one of the nails of Christ's crucifixion.' Metallurgical study of the iron core in 2003 by Dr. Robert Feather of the University of London dated it consistent with iron of the 1st–7th centuries. The Vienna lance was used in the coronation ritual of every Holy Roman Emperor from Frederick II (1220) until Francis II (1804). Now housed in the Schatzkammer (Imperial Treasury) of the Hofburg Palace.