March 3 Japan celebrates Girl's Day called "Hina Matsuri".

March 3rd is Japanese Girl's Day called hina-matsuri. It's a celebration for Japanese girls, and Japanese Boy's Day is May 5th in Japan. People display a set of hina dolls and props in the house, wishing girls' healthy growth and happiness. Traditionally, parents or grand parents of a newborn girl buy a set of gorgeous hina dolls unless they have special dolls, which are inherited from generation to generation. Hina dolls are dressed in Japanese ancient costumes and are displayed on the shelves of a stand covered with a red carpet usually from the end of February to March 3rd.
Hina-matsuri is also called momo-no-sekku, which means a festival of peach blossoms. Peach blossoms, shiro-zake (white rice wine), and hishi-mochi (diamond shaped rice cakes) are placed on the stand with hina dolls. Hishi-mochi are colored in pink (implies peach flowers), white (implies snow), and green (implies new growth).

Traditionally, girls in Japan invited their friends to a home party and had a good time. Many people still prepare a special meal for girls on this day. Common food for hina matsuri are chirashizushi, clam soup, sakura-mochi, and so on.

Source: About.com