Santa Maria delle Grazie (“Holy Mary of Grace”) is a lovely, if initially unassuming, 15th-century terracotta-stone church and convent located in Milan, Italy. While every brick of the church is rightly regarded as an architectural and artistic jewel, there’s something special about the north wall in the dining hall that led to the building’s designation as a UNESCO World Heritage Site.
On the night of August 15, 1943, an Allied aerial strike partly destroyed the site — that north wall was one of the few left standing, having been protected since the start of World War II by sandbags and scaffolding.
Why is that wall so important?