Ключевые слова: architecture, blue hour, building, church, city, city hall, cityscape, cologne, cologne city hall, europe, germany, great saint martin, gro st martin, historic, historical, history, illuminated, illumination, kln, landmark, light, lights, night, north rhinewestphalia, reflection, rhein, rhine, river, river bank, riverbank, riverside, romanesque, sightseeing, tourism, tourist attraction, tower, town hall, travel, travelling, urban, water, waterfront,