'Plastic King' Robert Bezeau has built the world's first plastic bottle castle. The Canadian's four-storey fortress on Panama's Bocas del Toro island shows how plastic waste can be made into low-cost sustainable housing. He's also building an eco-village using the same method.

Robert was the first foreigner to win the Environmental Excellence Award in Panama for his project, which educates children and creates incentives for them to pick up plastic waste.

Video journalist: Hannah Gelbart