June 30th is the day of Minazuki which is a kind of Japanese sweets. It relates to Nagoshi no Harae(夏越の祓). Harae (祓) is the general term for rituals of purification in Shinto. There are Harae on the last day of June and December, which are called Oharae. Oharae in June is Nagoshi no Harae. On this day, people in Kyoto eat Minazuki to remove sins and impurities and pray for good health during the second half of year.