14March, 2017 U.S.
3.14159265359.... need we go on? Celebrated on March 14 each (yes, that's 3-14), Pi Day not only commemorates a very special number but also celebrates the birthday of the great scientist and mathematician Albert Einstein. Pi was first calculated by Archimedes of Syracuse (287–212 BC), one of the greatest mathematicians of the ancient world. These days, all of the numerical fun is sometimes accompanied by delicious food items such as pizza pie, fruit pie, and even pot pies! So please channel your inner math geek and get ready to calculate, eat, and celebrate everybody's favorite never-ending number.