An arch bridge is a type of bridge that uses a curved structure to support its weight. The arch shape helps distribute the load evenly, allowing the bridge to span long distances without needing many supports. This design is not only strong but also visually appealing, making it a popular choice for both modern and historic bridges. One famous example of an arch bridge is the Sydney Harbour Bridge in Australia. Built in the 20th century, it showcases the beauty and strength of arch design. Arch bridges can be made from various materials, including stone, steel, and concrete, making them versatile for different environments.