In the 19th century, the archaeologists tasked with excavating Pompeii and Herculaneum ran into a problem: Everywhere they turned, they found erotic art, from frescoes of copulating couples to sculptures of nude, well-endowed gods.At a time when sex was widely considered shameful or even obscene, officials deemed the images too explicit for the general public. Instead of placing the artifacts on view, staff at the Museo Archeologico Nazionale di Napoli stashed them in a secret room closed to all but scholars and, according to Atlas Obscura, male visitors willing to bribe their way in. Between 1849 and 2000, the works...