Worldcon is the annual convention of the World Science Fiction Society (WSFS). It was first held in 1939 and, after a hiatus during WWII, has been held continuously since 1946. The sites of future Worldcons are decided by WSFS members via a bidding process.
The currently selected Worldcons are shown below. Click on the appropriate image to go to that convention’s website. For details of bids for forthcoming Worldcons click here.