Haus des Meeres (aquarium and vivarium)
Vienna had to deal with a lot of problems post WWII and one of them was what to do with the flak towers or bunkers. These were giant concrete blockhouses with walls 3.5m thick, built to house air defences to counter bombing raids by the allied forces.

Entrance. © Mark Brownlow
It’s not cheap, with adults paying just over €9 for an entrance ticket, but it’s an excellent way to kill an hour or two in wet weather, particularly if you have kids. Since it’s located just off one of Vienna’s major shopping streets (Mariahilfer Straße), you can combine a trip with a shopping expedition.
Highlights of the exhibition are:

Tropical house © Mark Brownlow
A vivarium with snakes, lizards, frogs, giant spiders and crocodiles. The most impressive exhibit is the albino python and its friend, which are BIG. There’s also a Chinese giant salamander, which is quite stunning when you’re used to the typical salamanders you get in your garden pond. They don’t call it giant for nothing.

Python. © Mark Brownlow
The rest of the tower is filled with tropical, Mediterranean and local fish, sea anemones, urchins, lobsters, starfish and other non-fish denizens of the water.

Piranhas. © Mark Brownlow
Address: Haus des Meeres, Esterhazypark, Fritz-Grünbaumplatz 1, 1060 Vienna
Website: http://www.haus-des-meeres.at/ (includes a complete version in English)