Ключевые слова: architecture, bridge, city, cityscape, color, day, douro, efficient, electric, electricity, europe, fast, light, metro, modern, new, oporto, outdoors, people, platform, porto, portugal, portuguese, rail, railroad, railway, rapid, river, scene, sky, speed, station, stop, street, streetcar, subway, technology, track, train, tram, tramway, transport, transportation, travel, trolley, underground, urban, vehicle, view, yellow,