Philcon

Philcon, also known as the "Philadelphia Science Fiction Conference", is an annual three-day science fiction convention held at the Crowne Plaza Hotel in Cherry Hill, New Jersey. The convention is run by the Philadelphia Science Fiction Society (PSFS). 
History.
In 1936, a half dozen fans came down from New York by train for the first intercity meeting of fans ever held. A picture taken of the group at Independence Hall has appeared in a number of the histories of science fiction fandom. They held a business meeting at the house of Philadelphia fan Milton A. Rothman, electing Rothman as chair and New Yorker Frederik Pohl as Secretary. Since Philadelphia had been the site of the 1936 Democratic and Republican National Conventions, they declared themselves the Philadelphia Science Fiction Convention. Part of the group went to John Baltadonis' home to examine his art collection and the printing press used to publish the PSFS newsletter. At Rothman's house, the group talked about science fiction and played craps. On the way back to the train station, some of the attendees sang early filk songs. One of the attendees, John B. Michel published an account of the day, the first convention report, in a New York fanzine:
Some fan historians claim that the 1936 Philadelphia Science Fiction Conference, a.k.a. Philcon, was the first science fiction convention ever held. Others, such as Fred Patten and Rob Hansen, make this claim for the January 1937 event in Leeds, England, organized by the Leeds Science Fiction League, which was specifically organised as a conference, with a program and speakers. Out of this came the first incarnation of the British Science Fiction Association.
Philcon in 2020 held a virtual convention due to the COVID-19 pandemic.
Philcon Worldcons.
The World Science Fiction Convention, or Worldcon, has been held in Philadelphia three times: