Butterfly House (Schmetterlinghaus)A warm art-nouveau glasshouse in the Burggarten where hundreds of tropical butterflies fly freely around you. Small, magical and quick; a lovely short stop in the centre. Free under 3.
Schönbrunn Zoo (Tiergarten)The world's oldest zoo, in the grounds of Schönbrunn Palace, home to giant pandas, polar bears and a rainforest house. Beautiful, big and an easy full day; combine with the palace gardens. Free under 6.