Shichi Go San Festival

November 15th is the Shichi-Go-San Festival in Japan,  a special day for three and five-year-old boys and three and seven-year-old girls. These ages are seen as important stages in a child's growth. 

On this day, prayers are offered at the shrine for the healthy and happy futures of the children, most children who visit the shrine will wear traditional dress or at the very least a new set of 'best' clothes.  As its not a national holiday the festival is observed on the nearest weekend to the 15th. 

Interesting fact - odd numbers are seen as lucky in Japan.