At long last, the Plastiki sets sail (photos)

SAUSALITO, Calif.--At 9:30 a.m. PDT Saturday, precisely on time, the Plastiki, a "boat made of 12,000 plastic bottles" and the brainchild of banking heir David de Rothschild, set sail from a berth here in this town just north of the Golden Gate Bridge.

The Plastiki is not just the world's first boat made buoyant by discarded soda bottles. It's also a statement about the world's garbage problem, and the fact that most plastic bottles are thrown away rather than recycled.

The intent is to sail the boat 11,000 nautical miles from Sausalito to Sydney, Australia. It is carrying about 1,000 liters of water, meaning the crew will have to stop from time to time to resupply. But they have fishing rods onboard, so at least some of their food, in theory, will come from the sea.

Among the inspirations for the project, in addition to bring attention to the way humans are treating our environment, is the Kon-Tiki expedition, Thor Heyerdahl's 1947 trip across the Pacific in a boat that was a reproduction of an Inca raft.

In keeping with tradition, the Plastiki will pay even more homage to Heyerdahl. Among the six crew members is Olav Heyerdahl, Thor's grandson.

Here, the Plastiki is seen as it has just sailed underneath the Golden Gate Bridge and heads for the Pacific. Its journey has just begun.