Bridge Building (Civ1)

Bridge Building allows the building of roads over rivers for increased traveling speed.
It is a prerequisite of Railroad.
== Civilopedia entry ==
An important measure of the advancement of any civilization was the internal Construction improvements built to facilitate trade and communication. The Roman Empire was renowned for its roads, aqueducts, and other structures that linked the frontiers to the capital. Bridge Building was greatly advanced by the Romans, and rediscovered in the West by medieval engineers many years later. The first Iron bridge was built in England in the late 18th Century, and Bridge Building techniques advanced rapidly to meet the demands of the expanding Railroads of the 19th Century.