Cathedral Window

This work is a stained glass window in the south transept of Cologne Cathedral in Altstadt-Nord, Germany. The glazing consists of more than eleven thousand individual squares of broad sheet glass, arranged in seventy-two color shades and together filling an area of roughly 106 square meters.

The current glazing was installed in 2007 after the removal of the 1948 ornamental windows. Those postwar windows had previously replaced the original panes from 1863, which had been destroyed by bombing during the Second World War.

The name refers to its position in the south transept, where daylight streams through the colored squares and casts geometric patterns on the stone floor below. Visitors often sit on nearby benches and watch how the patches of light shift with the sun's movement, painting the medieval architecture around them with changing colors.

The window looks most alive during morning hours, when direct sunlight floods through the squares and throws strong patches of color onto the floor. On cloudy days the colors become softer, allowing the geometric arrangement of individual glass pieces to stand out more clearly.

The arrangement of colored squares follows a random pattern generated by a computer program, while each individual piece was crafted using centuries-old glassmaking techniques. This combination of digital planning and manual execution makes every square a traditionally crafted element within a modern composition.