In Europe and America, the 18th or 21st birthday marks the beginning of adulthood and therefore it is usually celebrated a little bigger than a “normal” birthday. In Japan, there is a day for all teenagers reaching the age of maturity, which is 20, to celebrate together. The coming of age day (成人式).

The coming of age day is a Japanese national holiday, held annually on the second Monday of January. It is held in order to congratulate and encourage all those who have reached the age of 20 over the past year, and to help them realize that they have become adults. 

Coming of age ceremonies have been celebrated in Japan since at least 714 AD, when a young prince donned new robes and a hairstyle to mark his passage into adulthood. The holiday was first established in 1948, to be held every year on January 15. In 2000, Coming of Age Day was changed to the second Monday in January.

Until recently, all young adults attending the coming of age ceremony were exactly 20, having held their 20th birthday after the previous year’s Coming of Age Day but before (or on) the present Coming of Age Day. Coming of age ceremonies mark one’s coming of age, which reflects both the expanded rights but also increased responsibilities expected of new adults. The ceremonies are generally held in the morning at local city offices throughout Japan. 
On coming of age day, girls usually wear kimonos and sandals and set their hair so don’t be surprised when you see a lot of fancy dressed young women in the streets today.