The Denver Zoological Gardens was founded in 1896, when an orphaned American black bear cub was given to the mayor. The mayor gave the rambunctious cub to keeper of the City Park, Alexander J. Graham who began the zoo with the cub. Other animals at the zoo included native waterfowl at Duck Lake, antelope, prairie dogs and a flock of Chinese pheasants. A population of red squirrels was added to the zoo in 1905, and completely destroyed the bird population. The squirrels were then trapped and released into the Denver Mountain Park.
In 1906, Denver mayor Robert W. Spears decided to do away with the bars on the habitats and replace them with concrete rocks, waterfalls and trees. City landscape architect Saco DeBoer was hired to draw up plans for the renovation, and Victor H. Borcherdt was brought on to act as director of the zoo. Borcherdt was instrumental in the construction of the Bear Mountain exhibit, which he designed between the years of 1917-1918.
The Bear Mountain exhibit stands 43 feet tall and 185 feet long and the cost of construction was approximately $50,000. The structure was constructed using dyed and textured concrete forms which were cast from Dinosaur Mountain in Morrison, Colorado. To enhance the natural appeal of the habitat, hidden moats replaced bars; native plants and a stream were also added. The Bear Mountain exhibit established the Denver Zoo as a leader among American Zoos.
Using funds from the Works Project Administration, the zoo made one notable addition, Monkey Island which was constructed in 1937. During the following years, very little was done to modernize the zoo and it was in poor condition. However, with the election of Mayor Quigg Newton, Saco DeBoer was rehired to devise plans for the rebirth of the zoo. During the 1950's, the zoo overhauled Monkey Island, expanded and improved the grounds and exhibits and today is a world-class facility.
The zoo has continued to grow and in recent years has added some very significant new exhibits. In 2005, Predator Ridge exhibit was constructed. The display is representative of the African Savannah and has the ability to rotate between different predators such as lions, hyenas and African wild dogs. Complete with overlapping scents, the exhibit provides environmental enrichment for the various animals.
Opening in 2009, the Asian Tropics exhibit is the largest and most expensive addition yet. Constructed at a cost of $40 million, the exhibit houses Asian elephants and other larger animals, in an outdoor rotational habitat. The exhibit will also include Indian Rhinoceros, Malayan Tapirs, Black leopards, Muntjacs, Asian elephant cows and many other types of animals.
The Denver Zoo is open 365 days a year and summer hours are from March 1st through November 1st, from 9 am until 5 pm, and winter hours are from November 2nd through February 28th, from 10 am until 4 pm. Parking at the facility is free of charge, the zoo is fully handicapped accessible and provides picnic and concessions areas located conveniently throughout the park.