The Biotope City neighborhood in Vienna is attracting a lot of attention, visits and tours are the order of the day. But most of the sustainable and climate-efficient features are not easily or not at all visible. They are ‘hidden treasures’. In order to track them down, the IBA Vienna has compiled a small booklet that can be read online on the IBA site – and is also available in paper form from the IBA or the Biotope City Foundation if required.