What is the "Holi" event that just showed up on my Calendar?

Something called "Holi" is now scheduled on my Calendar for March 2, 2018 and I can't get rid of it, is this a mistake?

The "Holi" event scheduled for March 2nd, 2018 is not a mistake, Apple recently added it because it is a Hindu spring festival also known as the "festival of colors" widely celebrated in India. Like other holidays on the Calendar, you can't delete it.