June 21, 2010 -- Cheers and dancing erupted among a huge crowd of New Agers and neo-pagans gathered at Stonehenge early Monday morning as the first rays of sunlight peaked through the clouds.
This sunrise marked the start of the summer solstice, the longest day of the year and the beginning of summer.
About 20,000 people had been celebrating the coming of the dawn since the night before with an all-night party at the prehistoric site. Thousands gather for the annual event, as they wait for the rising sun at the Heel Stone, a pockmarked pillar just outside the circle.
The celebrations haven't always been so welcoming. Violent clashes between police and revelers in 1985 forced English Heritage, who manages and maintains Stonehenge, to close it to the public. English Heritage reopened it to celebrations in 2000, and the event has remained largely peaceful, although arrests were made this year.
This celebration, carried out today with bonfires, dances and courtship rituals, is a modern twist on solstice celebrations, or the coming of summer, which were once a traditional holiday on the pre-Christian calendar.
Solstice celebrations are tied with agriculture and mark a key turning point in the growing season. They date back to the time of the ancient Egyptians -- the Great Pyramids were specifically placed so that the solstice sunset could be easily viewed from the Sphinx -- and continue to be recognized by many cultures around the world today.