The Eden Project in Cornwall, England, showcases 100,000 plants from around the world in two giant transparent domes, each recreating different climate conditions. The structures were an unprecedented accomplishment, taking two-and-a-half years to construct, and one of them is the world’s largest greenhouse. Eden's aim was to create something that not only encourages people to celebrate and understand the world we live in. More than one million people have visited this "living theatre of plants and people" each year since its opening in 2001.