The biggest water fight in the world!
This massive water fight is held in Myanmar and Thailand in South East Asia, and is part of celebrations for the Buddhist New Year.
Hundreds of thousand of people turn out every year to take part. Similar events also take place in Laos and Cambodia.
How did it begin? Traditionally at this time of year, people would pour water over statues of Buddha, but it's now evolved into this!
And it certainly looks like a lot of fun.