We aim to provide empirical data regarding the role of various sex-on-premises venues for gay men in the spread of HIV infection and homosexual activity with casual partners at different (public) venues was assessed. A questionnaire was filled out by participants in a cohort study in Amsterdam, The Netherlands. Questions were asked regarding sex in private homes, baths, cruising areas, darkrooms, cinemas, and hotel rooms. The majority of the 410 men who had sex with casual partners had done so in private homes (67.8%). However, cruising areas, baths and darkrooms were also highly frequented. Three general 'scenes' of venues frequented could be distinguished, and characteristics of men frequenting different types of venues were found to differ. Men who reported unprotected anal sex did so for only one type of venue. Private homes were the locations where most men engaged in high-risk behaviours. However, the number of partners practising unprotected anogenital sex was highest in (semi) public venues.