In 1916 Dr. Harry Wegeforth heard the roar of a lion left over from a World’s Fair in San Diego. At that moment, the prominent physician decided a zoo was needed in San Diego. 90 years later, and world-famous, the San Diego Zoo is still innovating exhibits for more than 4000 animals, while entertaining millions of visitors. From Australian koalas to Arctic polar bears, the San Diego Zoo celebrates 90 years of animal adventure. Open 365 days a year, the San Diego Zoo welcomes San Diego families as well as visitors from around the world.