Machinery and assembly for the reconstruction of the Cathedral Notre Dame, burned down in April 2015

machinery notre dame cathedral paris restoration fire damage reconstruction rebuilding renovation repair spire roof vault stonework glass windows ornamentation facade gargoyles rose windows stained glass frescoes statues sculptures carvings finials stonemasons architects engineers artisans craftspeople funding donations sponsors government support heritage site world heritage cultural significance religious significance tourist attraction iconic landmark gothic architecture history design style construction techniques challenges progress