his article is about the structure. For the card game, see . For other uses, see and .The in , Suffolk, EnglandUnderneath the in , The old stone-made over the in ,
A bridge is a structure built to a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually something that is otherwise difficult or impossible to cross. There are many different designs of bridges, each serving a particular purpose and applicable to different situations. Designs of bridges vary depending on factors such as: the function of the bridge, the nature of the where the bridge is constructed and anchored, and the material used to make it and the funds available to build it.
The earliest bridges were likely made with fallen trees and . The people built bridges across marshland. The (dating from the 13th century BC, in the ) is one of the oldest still in existence and use.
ContentsEtymology[]The in (13th century BC), one of the oldest in existenceThe bridge over is an example of (1502–1722) bridge design. , .The 13th century spans the .
The traces the origin of the word bridge to an word brycg, of the same meaning. The word can be traced directly back to Proto-Indo-European *bʰrēw-. The word for the has a different origin.
History[]Seasonal bridge north of , H.P., India. 2010Bridges in ,
The simplest and earliest types of bridges were . people also built a form of across marshes; examples of such bridges include the and the in England, approximately 6000 years old. Undoubtedly, ancient people would also have used ; that is a that fall naturally or are intentionally felled or placed across streams. Some of the first man-made bridges with significant span were probably intentionally felled trees.
Among the oldest is the crossing upper in Switzerland; the prehistoric timber piles discovered to the west of the date back to 1523 BC. The first wooden footbridge led across Lake Zürich, followed by several reconstructions at least until the late 2nd century AD, when the built a 6-metre-wide (20 ft) wooden bridge. Between 1358 and 1360, , built a 'new' wooden bridge across the lake that has been used to 1878 – measuring approximately 1,450 metres (4,760 ft) in length and 4 metres (13 ft) wide. On April 6, 2001, the reconstructed wooden footbridge was opened, being the longest wooden bridge in Switzerland.
The is one of four Mycenaean bridges part of a former network of roads, designed to accommodate , between the fort of Tiryns and town of Epidauros in the , in southern Greece. Dating to the Greek (13th century BC), it is one of the oldest still in existence and use. Several intact arched stone bridges from the can be found in the Peloponnese.
The greatest bridge builders of antiquity were the . The Romans built arch bridges and that could stand in conditions that would damage or destroy earlier designs. Some stand today. An example is the , built over the river , in . The Romans also used , which reduced the variation of strength found in natural stone. One type of cement, called , consisted of water, , sand, and . and bridges were built after the Roman era, as the technology for cement was lost (then later rediscovered).
In India, the treatise by mentions the construction of dams and bridges. A bridge near was surveyed by . The bridge was swept away during a flood, and later repaired by Puspagupta, the chief architect of emperor . The use of stronger bridges using plaited bamboo and iron chain was visible in India by about the 4th century. A number of bridges, both for military and commercial purposes, were constructed by the administration in India.
Although large Chinese bridges of wooden construction existed at the time of the , the oldest surviving stone bridge in China is the , built from 595 to 605 AD during the . This bridge is also historically significant as it is the world's oldest stone segmental arch bridge. European segmental arch bridges date back to at least the (approximately 2nd century AD), while the enormous Roman era (105 AD) featured open-spandrel segmental arches in wooden construction.[]
