Ohi (όχι) Day is a national public holiday, commemorated on the 28th October every year. It was on this day in 1940 when the then Prime Minister of Greece, Ioannis Metaxas denied Italian dictator Benito Mussolini’s request to allow Axis forces to enter Greece. As a result, Italian troops stationed in Albania attacked the Greek border, leading to Greece's participation in World War II.

Thus, that decision is commemorated each year as a day that represents heroism and bravery for Greeks all over the world. Military and student parades take place every year, schools and work places are closed, and many public buildings, as well as residences, are decorated with the national flag.