What architectural alteration in 1652 damaged the lower part of The Last Supper?
Answer
a door was cut through the wall
The architectural alteration that damaged the lower part of The Last Supper in 1652 was a door cut through the wall.
The doorway was opened through the lower central portion of the refectory wall, destroying the area where Leonardo had depicted Jesus’s feet. The intervention occurred nearly 160 years after Leonardo completed the mural and reflects how little the painting’s importance and vulnerability were understood at the time.
The doorway was later bricked up, but its irregular arch-shaped outline remains visible near the bottom center of the composition. Early copies of the mural help scholars reconstruct the lost feet and suggest that they were arranged with symbolic reference to Christ’s coming crucifixion.
This damage is separate from the mural’s gradual deterioration. Leonardo’s experimental technique—tempera applied to a dry wall—made the surface unusually fragile, while dampness from the building’s masonry and surrounding environment caused paint to peel. Later damage included wartime bombing and careless restoration campaigns.