The World Science Fiction Convention is the longest running SF convention in the world. The first Worldcon, retrospectively known as Nycon I, was held in New York in 1939 with an attendance of 200 people. The Guest of Honour was Frank R. Paul. The convention has taken place every year since except during the Second World War, usually around American Labour Day weekend. By the mid-1970s attendance rose to about 4,000-5,000 fans, with more or less attendees depending on the host city.
Gender Shifter Social Sci-Fi with a Bit Romance and a Touch of Gore