From the issue Afternoon Delight
Didja hear that? There are some curious sounds near San Francisco's Marina Green—and the closer you get to the water, the more these sounds seem to rise from the sea. Sure enough, the ocean is making music using the Wave Organ, a man-made instrument with twenty-five pipes created by the Exploratorium's Pete Richards. This hidden surprise is located on a jetty behind the Golden Gate Yacht Club. Extending into the water at various heights, the Wave Organ's pipes make noise whenever the Pacific waves flow in and out of them. Hold your ear close to the pipes and their ports to best appreciate their full range of sound. There are no directional signs leading to this musical piece of magic; you just have to follow your ears.
The organ is most active acoustically during high tides and becomes subtle as the water level drops. Click here for a map.