Bat Appreciation Day
Bat Appreciation Day is held on April 17. This event in the second decade of the month april is annual.
Foursquare Day on April 16 (4sqDay or Foursquare Day was coined by Nate Bonilla-Warford, an optometrist from Tampa, Florida on March 12, 2010 being the 4th month and the 16th being equal to four squared. The idea came to him while "thinking about new ways to promote his business". FitBy4sqDay has been a quest by foursquare users to reach new fitness goals and live in a healthier way and is an excellent opportunity for local businesses to shine);
Blah Blah Blah Day on April 17 (is the opportunity to stop procrastinating and get to grips with all those stalled projects and broken promises right now);
Ford Mustang Day on April 17 (The Ford Mustang was first introduced to the world in April of 1964);
Auctioneers Day on April 17 (is one of the world’s most ancient professions, having begun more than 2,000 years ago. Third Saturday of April);
Dancing Cow Day in Denmark on April 18 (On the third Sunday of April);
World Amateur Radio Day on April 18 (Every April 18, radio amateurs worldwide take to the airwaves in celebration of World Amateur Radio Day. It was on that day in 1925 that the International Amateur Radio Union was formed in Paris);