Garlic Day is held on April 19. This event in the second decade of the month april is annual.
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);
Dancing Cow Day in Denmark on April 18 (On the third Sunday of April);
World Bicycle Day on April 19 (The events of the first LSD trip in April 19, 1943, now known as “Bicycle Day”, after the bicycle ride home, proved to Hofmann that he had indeed made a significant discovery: a psychoactive substance with extraordinary potency, capable of causing significant shifts of consciousness in incredibly low doses);