July 7th: 七夕 (Star Festival)

July 7th in Japan is Tanabata.  Tanabata is known as the “Star Festival” and is typically held on July 7. It traces its roots to a Chinese legend where the star Altair and the star Vega, which are usually separated on opposite sides of the Milky Way, are allowed to come together on this day once a year.

The festival began some time during the feudal period after combining with local customs and was originally celebrated by the Imperial Court before becoming celebrated by commoners as well. Because the holiday used to be celebrated according to the lunar calendar, some places in Japan will celebrate Tanabata on August 7 instead.

A popular activity during the celebration is to write your wishes on a piece of paper (tanzaku) and hang it on a bamboo tree in the hopes of having your wish come true. The biggest festivals are located in Sendai and Hiratsuka which take place in August and July respectively.

Reference:
日本まるごと辞典【改正第二版】p.27