An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side. A viaduct may be made from a series of arches, although other more economical structures are typically used today.
A double-arch stone bridge in Nagasaki, Japan
The Roman Alcántara Bridge, Spain (built 103-106 AD)
The Anji Bridge, 6–7th century AD
Segovia Aqueduct (c. 100 AD)
An arch is a curved vertical structure spanning an open space underneath it. Arch can either support the load above it or perform a purely decorative role. The arch dates back to fourth millennium BC, but became popular only after its adoption by the Romans in the 4th century BC.
Gateway Arch
A complex funicular model (Church of Colònia Güell by Gaudi, 19th century)
Arcades of Pont du Gard (Roman)
Separating arches in the St. Zeno church [de]