Children are usually told to stay away from dirt.
But at one festival in China, it is all about getting as filthy as possible, like this young reveller getting smeared with black ash in Pu'er, Yunnan province, on Monday.
The Monihei (making you black) Carnival is celebrated by the ethnic Wa people each year on May 1.
According to tradition, the more mud - which is commonly used nowadays - you have on you, the more fortune and good health will be bestowed upon you, said the Daily Mail.
Soot, blood and soil were traditionally used.
The Wa people, one of 56 ethnic minorities in China, believe that humans came from caves. By applying mud or dirt on different people, it is said that a different wish is granted or a gift bestowed.
For example, for the elderly, it would be a wish for them to live a long life.
For women, it would be a gift of beauty - being dark is a sign of beauty for the Wa people, who believe it signifies hard work.
For children, it would be safety and health.
After getting covered in mud, festivalgoers are usually treated to a feast and traditional performances.