vienna cityscape with skyline of historic and modern buildings

apartment apartments architecture austria austrian autumn block blocks blue building buildings business center city cityscape cloud clouds cloudy colourful complex concrete downtown europe facade facades flat flats garden gardens glass gray grey high highrise house houses housing landscape large leaning mall modern office offices old overcast panel plain red residential rise roof rooftop shopping sky skyline skyscraper skyscrapers sloping steel structure tall terrace terraces tile tower towers town urban vienna viennese view wall white wien window windows