Although many nineteenth century misconceptions about the foreskin have been dispelled since Douglas Gairdner showed that infantile phimosis was not a congenital defect, other old ideas have proved more persistent. Among the most ubiquitous are the proposition that ritual or religious circumcision arose as a hygiene or sanitary measure; and the related idea that allied troops serving in the Middle East during the Second World War were subject to such severe epidemics of balanitis that mass circumcision was necessary. Both these claims are medical urban myths which should be firmly laid to rest.