St John's Night is celebrated on the eve of the feast day of St John the Baptist on June 23. This traditional holiday is also known by other names, such as Midsummer's Eve, Summer Solstice, and Johannistag. In some cultures, it's celebrated as the longest day of the year and a time to welcome the summer season, where people light bonfires, dance, and sing. In some parts of the world, it's called St. Hans Aften, Noche de San Juan, and Juhannus. Different countries have their unique way of celebrating this day, but the meaning behind it remains the same- a joyous celebration of life.