Ключевые слова: architecture, building, chicago, chicago downtown, city, cityscape, cloud, commercial building, corporate headquarters, daytime, downtown, flying, grass, green, headquarters, high rise, large, metropolis, millenium park, no person, office building, outdoor, park, plant, sears tower, sky, skyline, skyscraper, spire, st regis chicago, standing, street, summer, tower, tower block, travel 875 north michigan avenue, tree, urban, water, willis tower, window,