Cruising provided a way for gay men to solicit sexual encounters while minimizing the risk of being caught by the police. Prior to the Sexual Offences Act 1967, this illegality meant that many gay men could not live openly as homosexuals. Cruising came about owing to the illegality of homosexual acts in the United Kingdom. So-called 'cruising grounds' or 'cruising sites', where gay and bisexual men meet at a public place to cruise for sex, originated in the late 1600s (from the earliest known records, although it most likely originated much earlier) and has continued to the present day. He believes that the first gay cruising grounds and gay brothels in London may have sprung up in the early 17th century theatres were sometimes denounced as such by moralists of the time. Rictor Norton, author of Mother Clap's Molly House (a reference to Margaret Clap), is one of the few historians to address the topic. The history of gay cruising is sparsely documented, as the illegality of gay sex meant that those who used such cruising grounds were likely to be discreet about them. 1.2 Areas with a history of gay cruising.