If you're under 25, you get a discount. The entry fee isn't too high, but it isn't cheap either. That being said, it's well worth it. You get really close to the animals and some of the exhibits really integrate you into the enclosure. It's well worth a visit. Their rainforest exhibit is the best I've been to, but it is ~100 Fahrenheit, so beware if your going in winter. Your camera will steam up for a while (try using the hand dryer looking unit outfront before going in to adjust it yo the temperature difference) and you'll want to take off your jacket.
Zurich zoo opening to the outside world in 1929, is one of the best zoos in Europe. Unique in the pavilion, raise the tropical rain forest birds, apes, reptiles and other types of animals, its life environment is built to simulate the natural environment in their habitat. Open new outdoor pavilion can see bears and proboscis raccoons, Zurich, which is another fascinating sights at the zoo. Snow leopard exhibited at the Zurich zoo in 2002, it also attracted many tourists to come to see the snow leopard.
A little bit of everything, and more poison dart frogs than I've ever seen. Two separate penguin exhibits, and all the basics in a just-right sized package. Massive elephant enclosure opening soon will be really nice. There's a petting zoo somewhere across the street - we missed it, but keep your eyes open if you want to make a whole day of it.