Situated at the north end of the Bronx Zoo, the Rainey Gates were completed in 1934 as a memorial to noted big game hunter Paul James Rainey. They depict stylized animals including polar bears, elk, turtles at the base, and a single majestic seated lion at the very top.

The zoo was planned in two parts. At the north, five Beaux-Arts style animal houses surrounded Astor Court. Pictured here is the Elephant House, now the Zoo Center.

Even before the Bronx Zoo opened in the 1899, the Rocking Stone of Bronx Park was a popular attraction. The seven-foot tall, ten-foot wide piece of pinkish granite weighs 30 tons. As pictured here, the rock was finely balanced on the stone below it. With the strength of only a few it could be moved slightly (hence the name).

The zoo opened in 1899, with 843 animals and 22 exhibits. Today it is the home to over 4,000 animals. The Zoo's primary mission is for the conservation of wildlife.

As marked by the bird sculpture over the entrance, this building was the Large Bird House. In recent history, the Zoo's largest feathered friend was a gyrfalcon called Temujin, who can survive in temperatures below freezing.

The lions moved out of the Lion House in 1940 when they became residents of Lion Island. The Zoo has claimed since its inception that it would be dedicated to the study of zoology and the preservation of wildlife. Lion Island was one of the first naturalistic habitats that allowed animals to be kept out of cages.

The African Plains were the first exhibit in which animals were displayed in a "natural" setting. Predator and prey are separated by hidden moats while appearing to share ground.

Rhinoceroses, elephants, lions, tigers, and deer live in the Wild Asia, which opened on 38 acres of previously undeveloped land. You can traverse this terrain via monorail.

In 2011, a missing Egyptian cobra was found in an off-limits area of the Reptile House. It escaped for almost a week and was curled up only a few hundred feet from its home.

The Reptile House is the oldest building at the Zoo. Raymond Lee Ditmars, an amateur snake hunter who lived just south of the Zoo, was their first reptile curator. He contributed his collection of 45 snakes to the zoo when he was appointed.

And... a zoo doesn't come without controversy. The orangutan, like the ones pictured, had an unlikely roommate in the early 20th century. Ota Benga, a Mbuti man, was displayed as an exhibition in the Monkey House in 1906. He was previously on display at the American Museum of Natural History before being moved to the Bronx Zoo. He was released in less than a year after he arrived.

In 1902, a 7-month old jaguar chewed through his cage and escaped. The big cat supposedly terrorized a group of picnickers, quelling his appetite on... their abandoned sandwiches. Legend has it he got away by jumping into the Bronx River.

A heavy wind storm in the winter of 1995 collapsed the De Jur Aviary. 33 rare birds to escaped. Most of them had never lived in the wild. Fish were placed around the ruined cage to attract the lost gulls and Inca tern.

A resident elephant named "Happy," (after the Seven Dwarfs) is a frequent target to critique by various animal rights organizations. Happy, a highly social animal, has lived alone since her lifelong companion was euthanized.

Though a zoo doesn't come without controversy, the Bronx zoo has kept its mission of protecting wildlife for over a century since its opening. It continues to be the flagship park of the Wildlife Conservation Society and welcomes over two-million visitors each year.