NASFiC

NASFiC, the North American Science Fiction Convention was added to the Worldcon Constitution in the mid 1970s. It was intended to legitimatize the inevitable major convention in North America when the Worldcon was held in other parts of the world without encouraging the development of an American natcon, which would inevitably become a competitor to Worldcon.

The first NASFiC was held in Los Angeles in 1975 when the first Aussiecon was in Melbourne, Victoria, Australia. The second NASFiC (NorthAmericon) was in Louisville, Kentucky in 1979 when Brighton, England was selected for the Worldcon. The name "NASFiC" was coined by Tony Lewis.

Convention Dates Location GoHs
NASFiC (first) Labor Day weekend 1975 Los Angeles, CA Harlan Ellison
NorthAmericon '79 August 30 - September 3, 1979 Louisville, KY Frederik Pohl, George Scithers
LoneStarCon August 30 - September 2, 1985 Austin,TX Jack Vance, Richard Powers, Joanne Burger
CactusCon September 3-7, 1987 Phoenix, AZ Hal Clement, Marjii Ellers
ConDiego Labor Day weekend 1990 San Diego, CA Samuel R. Delany, Ben Yalow
Dragon*Con 1995 July 13-16, 1995 Atlanta, GA George Alec Effinger, Harlan Ellison, Timothy Zahn, Michael Whelan, Bjo Trimble
Conucopia August 26-29, 1999 Anaheim, CA Jerry Pournelle, Ellen Datlow, Richard Lynch, Nicki Lynch
CascadiaCon September 1-5, 2005 Seattle, WA Fred Saberhagen, Liz Danforth, Toni Weisskopf, Kevin Standlee
Archon 31 / Tuckercon August 2-5, 2007 Collinsville, IL Barbara Hambly, Darrell K. Sweet, Kevin Murphy, Bill Corbett, James Ernest, Elizabeth Covey, Barry Childs-Helton, Sally Childs-Helton, Nancy "Cleo" Hathaway, Lani Tupu, Richard Hatch
Reconstruction August 5-8, 2010 Raleigh, NC Eric Flint, Brad Foster, Juanita Coulson
Detcon1 Jul 17-20, 2014 Detroit, MI Steven Barnes, John Picacio, Bernadette Bosky, Arthur D. Hlavaty, Kevin J. Maroney, Helen Greiner, Bill Sutton, Brenda Sutton
NorthAmeriCon '17 July 6-9, 2017 San Juan, Puerto Rico DaĆ­na Chaviano, Tobias S. Buckell, Guy Consolmagno, Javier Grillo-Marxuach, George Perez, Paula Smith
Spikecon July 4-7, 2019 Layton, UT David Weber, Laurell K. Hamilton, Vincent Villafranca, Dragon Dronet, Susan Chang, Linda Deneroff, Bjo & John Trimble
2020 NASFiC August 20-23, 2020 Columbus, OH Brian Herbert, Kevin J. Anderson, Stephanie Law, Christopher J. Garcia, Marc Millis, Sue & Steve Francis

See also Noncon (fanspeak); the major difference being that the location of the NASFiC is determined by members of the Worldcon.