Ключевые слова: architecture, arms, asphalt, blue, building, capital, center, city, classic, clock, del, destination, door, europe, european, flags, gate, geography, highway, history, kilometer, kilometre zero, km, km0, landscape, madrid, modern, origin, pavement, plaque, puerta, puerta del sol, real, road, royal, sculpture, sidewalk, sign, sky, sol, spain, spanish, square, stone, sun, symbol, tourism, underground, urban, zero,