Four stained glass windows, badly damaged in the 2019 fire at Notre-Dame Cathedral, have been restored and are on their way back to the French capital after being restored at Cologne Cathedral in Germany. The windows, created by Jacques Le Chevallier in 1965, are due to arrive in Paris after Easter. The restoration, lasting around a year, was seen as a symbol of German-French cooperation. During the process, two major challenges needed to be faced, according to Barbara Schock-Werner, former Cologne Cathedral building master and coordinator for German aid in the reconstruction of Notre Dame. Firstly, the windows had been contaminated with lead, since the cathedral's roof was constructed with lead, which needed to be removed. Then, soot and dirt also had to be delicately removed without harming the depiction. The windows will reportedly undergo further restoration work in France before being returned to their original positions.