For years this Worldcon held the record for the largest attendance at any early science fiction convention , with 870 registered attendees , a figure which was not surpassed by another Worldcon until 1967 for Nycon 3 in New York City . By way of comparison , the previous year 's Worldcon , the Nolacon in New Orleans , had an attendance of 190
Nolacon
9th World Science Fiction Convention
10th World Science Fiction Convention