Maybe it’s all those negative ions in the sea air, which scientists say promote a feeling of well-being, even bliss. Or maybe it’s Siesta Beach’s sand, which is 99 percent pure quartz crystals, reputed to have magical healing powers. Or perhaps it’s the splendor of the sun setting over the Gulf as one week ends and another begins. Whatever their reasons, visitors and locals converge on Siesta Beach every Sunday evening about an hour before sunset to celebrate Drum Circle.

This weekly ritual, which started back in 1996, even has its own Facebook page, with more than 6,400 fans. The event attracts an eclectic crowd of performers and spectators. The musicians, who range from Willie Nelson lookalikes in bandanas and beards to clean-cut kids, beat on their drums in pulsating rhythm. Anyone can come; anyone can play. Inside the circle, a changing cast of characters dances, many in flowing, tie-dyed clothes. On a recent early winter night, most of them were twirling hula hoops, which flashed with LED lights as the sky grew dark.

Some spectators clapped in rhythm; others just stood and watched. Kids in bathing suits played in the sand; families set up lawn chairs and unloaded coolers. In a windbreaker and shorts, Mike Wright said he and his wife, who travel from Michigan every year for a week on Siesta, had just learned about the circle online and decided to check it out. “It’s different,” he said with a smile.

For many, the circle is both a social and spiritual event. One of the dancers, 28-year-old Christine Brolus, says going through “a traumatic experience” prompted her to seek out the circle last January, and she’s been coming ever since. “It’s such a good energy,” she said. “The masks come off people, and everyone gets the space they need and the unity they need.”

Whatever you come for, you’ll find a mellow atmosphere and engaging show—in the circle and in the sky, as the setting sun paints the scene with shades of pink, gold and purple. By an hour or so after sunset, the party is over—but it will start up next Sunday all over again.

In addition to the circle on Siesta Beach, there’s also a Drum Circle on Sunday evenings on Nokomis Beach.