River bridges are structures built to span a river, allowing people and vehicles to cross safely. They come in various designs, including beam, arch, and suspension bridges, each suited to different river widths and environmental conditions. River bridges play a crucial role in transportation, connecting communities and facilitating trade. These bridges are often constructed using materials like steel, concrete, and wood, depending on the design and location. Maintenance is essential to ensure their safety and longevity, as factors like water flow, weather, and traffic can affect their integrity. Notable examples include the Golden Gate Bridge and the Brooklyn Bridge.