A city skyline is the outline of a city's buildings and structures against the sky, often seen from a distance. It typically features a mix of tall skyscrapers, historic buildings, and other architectural elements that define the city's character. Skylines can vary greatly depending on the city's design, geography, and cultural influences. Many famous cities, such as New York City and Chicago, are known for their iconic skylines, which attract tourists and photographers. The skyline can change over time due to new construction, renovations, or urban development, reflecting the city's growth and evolution.