viaduct
/ˈvaɪəˌdʌkt/
noun
- A long bridge-like structure, typically consisting of a series of arches, that carries a road or railway across a valley or low ground.
- The train crossed the old stone viaduct high above the river.
- Engineers built a concrete viaduct to carry the highway over the canyon.
- The ancient Roman viaduct still stands and is used by pedestrians.