Tanabata, the "Star Festival", is kept on the seventh day of the seventh month (7 July in most of Japan, or August by the older calendar in some regions), and it celebrates a romance written in the sky. It derives from a Chinese legend, that of the weaver girl Orihime (the star Vega) and the cowherd Hikoboshi (Altair), lovers set on opposite banks of the Milky Way and permitted to meet only once a year, on this night, when a bridge is formed for them, provided the sky is clear. The tale reached Japan and merged with an indigenous weaving-and-purification custom, taking its written name Tanabata from an old word for a ceremonial weaving maiden.
The festival's best-known custom is the writing of wishes on strips of coloured paper, tanzaku, which are tied to freshly cut bamboo branches, often together with paper streamers and ornaments; after the festival the bamboo is traditionally floated on a river or burned, sending the wishes off. Originally associated with prayers for skill in weaving, sewing and the crafts, and for good handwriting and learning, the wishes are now for anything the writer hopes for. Towns hold large Tanabata festivals with elaborate streamers and decorations, and the sight of bamboo hung with paper wishes is one of the emblems of the Japanese summer.