Spiral Island

Spiral Island was a floating artificial island in a lagoon near Puerto Aventuras, on the East coast of Mexico south of Cancún. It was built by British expatriate Richie (or "Reishee") Sowa beginning in 1998; he filled nets with empty discarded plastic bottles to support a structure of plywood and bamboo, on which he poured sand and planted numerous plants, including mangroves. The island sported a two-story house, a solar oven, a self-composting toilet, and three beaches. 

He used some 250,000 bottles for the 66-by-54-foot structure (22x18m).

Spiral Island was destroyed by a hurricane in 2005. Mr. Sowa plans to build a stronger island in a more sheltered area.