Artis Royal Zoo, Amsterdam

The oldest zoo in The Netherlands, it houses a planetarium, an aquarium and a geological and zoological museum. For around 19 Euros (as of July 2012), you do get quite a lot. There is one part of the zoo where you can walk inside and have monkeys let lose, swinging around you. There was also a butterfly house, with many different species fluttering around. There are numerous feeding stations with fruit, so you can always get a close up when they are feeding. 

Inside the museum/aquarium building, there is a large variety of taxidermy animals, as well as species of fish from the rainforests to the reefs. The planetarium is interesting, but the voice over is in Dutch; so unless you speak fluent Dutch, I would probably give this a miss.

The zoo did house giraffes, zebra and gorillas, but was missing other big animals, such as elephants, rhinos and tigers. Overall, I thought you got a lot for your money.