Here's a complete list of events and holidays for the North American version of Animal Crossing: New Leaf. Below that, you'll find region specific holidays for international territories.
Calendar of Events:
January 1st: New Years
January 19th: Fishing Tournament
February 2nd: Groundhogs Day
February 11th: Festivale
February 16th: Fishing Tournament
March 16th: Fishing Tournament
March 17th: Shamrock Day
March 31st: Bunny Day
April 1st: April Fool's Day
April 13th: FIshing Tournament
April 22nd: Nature Day
April 26th: Weeding Day
May 5th: Boy's Day
May 18th: Fishing Tournament
June 15th: Bug Catching Tournament
June 16th: Father's Day
June 21st: Summer Solstice
July 20th: Bug-Off
August 4th: Fireworks Festival
August 11th: Fireworks Festival
August 17th: Bug-Off
August 18th: Fireworks Festival
August 25th: Fireworks Festival
September 2nd: Labor Day
September 19th: Autumn Moon
September 21st: Bug-Off
October 12th: Fishing Tournament
October 14th: Explorer's Day
October 31st: Halloween
November 16th: Fishing Tournament
November 28th: Harvest Festival
December 14th: Fishing Tournament
December 22nd: Winter Solstice
December 24th: Toy Day
December 31st: New Years Countdown
International Dates:
February 3rd: Setsubun (Japan)
March 2nd: Weeding Day (S. Korea)
March 3rd: Girl's Day (Japan)
March 19th: Father's Day (Spain/Italy)
April 5th: Arbor Day (Korea)
May 5th: Children's Day (Japan)
May 8th: Parent's Day (Korea)
May 15th: Teacher's Day (Korea)
July 7th: Starcrossed Day (Japan)
August 15th: Obon (Japan)
September 3rd: Grass Day (Japan)
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