Ostrava city as lost it's relationships to the medieval history of the city centre. There are not any historical places, spaces or palaces, with free public spaces like the old castles and palaces in the cities. In the place of the former German House, destroyed after the the World war II is a rest of public space, which could be a part of the city sustainability concept. The project let's the rest of the historcial garden there like a countryard between two houses of the new Sustainable Development Centre. The sustaiable concept is to let there be a free space in the highly dense block structure of the modern city.