Mimmo Jodice/CORBIS

Prostitutes almost certainly used the Lupanar’s five first-floor rooms. Each of these rooms had a raised masonry platform that served as a bed, complete with headrest. The classicist Andrew Wallace-Hadrill has argued that a building must have three features (masonry beds, erotic art and erotic graffiti) to be considered a brothel; the only structure in the ancient Roman world that satisfies all these criteria is the Lupanar.

Does this mean that the Lupanar was the only brothel in the Roman world? Not according to author Thomas McGinn, who argues that the Wallace-Hadrill criteria are too restrictive. If we take a number of factors into account—including the location of the building, population, the presence of erotica, and so on—it appears that Pompeii had about 20 brothels.