And the category is... reptiles, amphibians, fish and invertebrates. I know nothing about Mulhouse's collection, but I felt Hamburg's aquarium building is one of the most impressive parts of an otherwise somewhat disappointing zoo. The concept behind this poll is explained here: ZooChat Cup In summary, the rules of the game are as follows: - You may choose whatever criteria you like to decide how to vote, as long as it only relates to the category above. - You can use whatever resources you like to inform your vote, including Zoolex, Zootierliste, the ZooChat gallery, trip reviews, zoo maps, books and whatever else you can think of. You don't have to have visited both zoos to vote. - Votes are public and can be changed at any time before the poll closes. - The aim of the game is to provoke debate. Post explaining why you voted the way you did, and why others should join you. - Voting closes in seven days. - The one thing you can't do is vote based on anything other than the relevant category.