A railway viaduct is a bridge designed to carry trains over obstacles such as valleys, roads, or rivers. These structures are typically made of materials like concrete, steel, or stone and are built to support the weight of heavy trains while ensuring safety and stability. Viaducts can vary in design and length, with some spanning several kilometers. They are essential for maintaining efficient railway networks, allowing trains to travel smoothly without interruptions from the terrain. Famous examples include the Millau Viaduct in France and the Royal Albert Bridge in the UK.