Only four zoos are older:

They are in Philadelphia, Chicago, Cincinnati and Buffalo.

Fun fact:

The zoo's history begins with Erastus Ross, who donated 90 acres of land to the city of Binghamton, so that a park could be built.

In 1919, the cost of gas was $.25 per gallon. The cost to get into the Ross Park was free and so was the carousel! Entrance cost to the park is still free, as is the carousel, but there is a fee to get into the zoo.