The complex is dominated by two huge enclosures consisting of adjoining domes that house thousands of plant species, and each enclosure emulates a natural biome. The biomes consist of hundreds of hexagonal and pentagonal ethylene tetrafluoroethylene (ETFE) inflated cells supported by Geodesic tubular steel domes. The largest of the two biomes simulates a rainforest environment (and is the largest indoor rainforest in the world) and the second, a Mediterranean environment. The attraction also has an outside botanical garden which is home to many plants and wildlife native to Cornwall and the UK in general; it also has many plants that provide an important and interesting backstory, for example, those with a prehistoric heritage.