Ключевые слова: america, american, architecture, building, buildings, business, city, cityscape, district, downtown, financial, financial district, highrise, infrastructure, landmark, modern, office, office building, office buildings, pennsylvania, pittsburgh, pittsburgh pennsylvania, pittsburgh skyline, skyline, skyscraper, skyscrapers, steel city, structure, towers, united, united states, urban, usa, view,