In an event that a child visits the shrine where Mt. Fuji is enshrined for the first time, his or her parents buy Uchiwa fan called Hatsuyama Uchiwa in the annual festival held on the opening day of a mountain to climbers (usually June 1), distributing it to relatives for expressing their appreciation and telling relatives about their child's growth.
生まれて初めて富士山を祀る神社に参拝する行事で、山開きの日（多くは6月1日）の例祭に、初山団扇と呼ばれる団扇を購入して親類縁者に配り、子供の成長の御礼と報告を兼ねる場合が多い。