Foursquare Day was born in March 2010 as an idea that since 4 squared equals 16 that we should all all go out and check-in on foursquare on the 4th month and 16th day of the year, April 16th. A few weeks after the idea was hatched over 300 cities joined together to celebrate 4/16/10 as Foursquare Day!

On Friday March 11th we’re celebrating the anniversary of the start of the Foursquare Day idea by officially kicking off the countdown to Foursquare Day 2011, 4/16/2011! You can join us to kick off the countdown in three ways:

  1. Join us by watching our live Ustream starting at 7pm eastern.
  2. Join us at SXSW in Austin, Texas.
  3. Join us at 4sqday HQ South in Tampa, FL.

Foursquare Day creator Nate Bonilla-Warford will be broadcasting live on the Foursquare Day Ustream channel from Tampa and at 7pm eastern will officially kick off the countdown. We’ll have the Ustream broadcast playing live at our SXSW event and we hope that you will join us too, either online or in real life, and take part in kicking off the countdown to Foursquare Day 2011: When the world is your venue!