In 1453, Margaret of Charney, down on her luck, sold the duke of Savoy the Shroud of Turin. It’s the cloth said to have wrapped Jesus after the crucifixion. The Savoy began the Cathedral of Saint John the Baptist in the 1490s. The shroud lies there now, in a box inside a box behind bulletproof glass.

The cathedral seems to have two domes. Only the smaller one belongs to the church. The taller one is the Royal Palace’s, with a window looking in.

VoiceMap’s tours follow the shroud from Constantinople to the Savoy and weigh the evidence, from carbon dating to a theory about Leonardo da Vinci.