The Summer Solstice - also known as midsummer - occurs once a year on June 20th or 21th, when the sun is at its highest point in the sky for those on the northern hemisphere. It's the longest day of the year and the start of the Summer. It's also one of the few days English Heritage provides 'Managed Open Access' to Stonehenge: You get to spend the night in between the ancient stones and no access fee is charged.
