Summer Solstice date varies on or around June 20th-22nd
The June Solstice is the first day of Summer in the Northern Hemisphere where it is the longest day of the year, and the first day of Winter in the Southern Hemisphere where it is the shortest day of the year. The day of the June solstice varies from June 20 - June 22nd and most commonly falls on June 21st. The exact date depends on when the tilt of the earth on it's axis places the Sun at its northernmost point from the equator.
Celebrations around the world
Midsummers Day & Eve are celebrated in many cultures across the globe to bring in the summer and celebrate the harvest. Strawberries, bonfires and ancient sites like Stonehenge are common.