A sunny day in the bustling Potsdamer Platz in Berlin, Germany. A mixed-use neighborhood of residential and office buildings, public space, and community centers, it is a bustling area of urban design, architecture, and recreation. Tourists and citizens alike take in the sights of the modern facades, the asphalt roads, and the trees that provide shade for the bicycles and vehicles that drive by. Europe's metropolitan areas are unique and alive in their own ways.