The Bernward Doors () are the two leaves of a pair of Ottonian or Romanesque bronze doors, made for Hildesheim Cathedral in Germany. They were commissioned by Bishop Bernward of Hildesheim (938–1022). The doors show relief images from the Bible, scenes from the Book of Genesis on the left door and from the life of Jesus on the right door. They are considered a masterpiece of Ottonian art, and feature the oldest known monumental image cycle in German sculpture, and also the oldest cycle of images cast in metal in Germany. History Along with the Bernward Column, the doors are part of Bishop Bernward's efforts to create a cultural ascendancy for the seat of his diocese with artistic masterpieces in the context of the Renovatio imperii sought by the Ottonians. A Latin inscription on the middle crossbar produced after Bernward's death gives the year 1015 as the terminus ante quem for the creation of the doors: Creation and technical features Each leaf of the doors was cast as a single piece. Given the size (left: 472.0 x 125.0 cm, right: 472.0 x 114.5 cm, maximum thickness c. 3.5-4.5 cm) and enormous weight (both c. 1.85 tonnes) of the doors, this is a great achievement for its time. The raw material for the casting was Gunmetal, which consisted predominantly of copper (above 80%) with roughly equal parts of lead, tin, and zinc. To date material analysis has not been able to show which ore deposit the metal came from, though the ironworks at Rammelsberg near Goslar has been ruled out. Like their predecessors, the Wolfstür (Wolf's door) of the Aachen Cathedral and the Marktportal (Market Portal) of the Mainz Cathedral, the Bernward Doors were manufactured using the Lost-wax process, which puts exceptional demands on the workers of the casting workshop, since the mold can only be used once. The individual scenes of the doors were carved from massive wax or tallow tablets by modellers and then combined, supported by an iron frame, which is probably how the slight irregularities in the bands which divide the individual scenes came about. Even the doorknockers in the form of grotesque lion's heads with rings of grace in their mouths were included in the original mold rather than being soldered on later. Technical analysis has shown that the mold was stood on the long side and filled with bronze, so that the molten metal would