not breeding with matriarchal herds. The exhibit houses Asian elephants and other animals such as greater one-horned rhinoceros and Malayan tapirs, which rotate among different habitats in the same style as Predator Ridge. It includes more than of trails for the animals, and pools in the exhibit contain a total of . Northern white-cheeked gibbons swing directly over a boardwalk for visitors, traveling between three islands. Clouded leopards and sarus cranes live in nearby yards. The exhibit includes an indoor facility for smaller species like fishing cats, Asian small-clawed otters, great hornbills and green tree pythons and it provides important breeding facilities for the Indian rhino and Asian elephant in North America. The exhibit opened with two female elephants (Mimi and Dolly) and two bull elephants (Bodhi and Groucho). The zoo made history in 2013 by transporting Billy, a bull elephant from Belgium's Antwerp Zoo, via plane to the new exhibit. This marked the first time in over 30 years an Asian elephant had been imported into the United States and one of the few times the genetics of the European population would mix with the North American population. In October 2018, bull elephants Chuck and Jake came to the exhibit from the African Lion Safari in Ontario. This move made Denver's herd the largest Asian elephant bachelor herd in the world with five bulls. On February 22, 2020, the first greater one-horned rhino calf in the zoo's history was born as the result of artificial insemination. At its opening, the exhibit contained a waste-to-energy gasification system that allowed organic waste (i.e. uneaten food, animal waste, etc...) to be burned in an oxygen-deprived environment in order to create energy. The system powered outdoor hot tubs for the elephants and Denver Zoo's goal was to be "Zero Waste" by 2020, powering the whole facility with waste. Those involved with the project reported that no adverse byproducts would be released when the system was running but several surrounding residents were concerned that the gasification process would create an unpleasant odor around the zoo. These concerns resulted in ending the gasification project at Denver Zoo. Since the decision in 2015, the zoo is seeking partners to continue the project with offsite. Nonetheless, the exhibit and its buildings have received LEED Platinum certification from the U.S. Green Building Council. Harmony Hill Harmony Hill provides a habitat for grizzly bears modeled after the fictional Harmony