Gardens by the Bay, a 101-hectare horticultural attraction, contains 250 thousand rare plants in domed conservatories. There are two distinctively different conservatories: the Flower Dome and the Cloud Forest, designed by Wilkinson Eyre Architects. Both are planned for sustainable cycles in energy and water throughout Bay South Garden. The conservatories are the biggest climate-controlled greenhouses in the world and aim at creating cool growing environments in a pair of glasshouses.