A Roman bridge is a type of bridge built during the time of the Roman Empire, primarily to facilitate transportation and trade across rivers and valleys. These bridges were known for their impressive engineering, often constructed using stone, concrete, and arches, which allowed them to span large distances while supporting heavy loads. Many Roman bridges are still standing today, showcasing the durability of their design. Notable examples include the Pont du Gard in France and the Alcantara Bridge in Spain. These structures not only served practical purposes but also symbolized the power and ingenuity of Roman architecture.