Although moats were regularly used in the design of exhibits at the Cleveland Zoological Park in the 1960s, it was not a new idea. Detroit's zoo, which Cleveland zoo advocates often used as a shining example of modern design, employed this approach to exhibit construction in the late 1920s and 1930s. Under the advisement of Carl Hagenbeck's son, Heinrich, the Detroit Zoo prominently used moats to offer visitors an uninterrupted view of animals in a simulated habitat.
