What is a Causeway?

A causeway is a narrow raised pathway that has sand, marshland or water underneath it. Causeways may be a natural part of a landscape or they may be created with bridge construction methods. Some of these roadways may be a part of an irrigation system such as a canal. One of the earliest forms of roads, causeways exist worldwide.

The Giant's Causeway in Northern Ireland was formed naturally in the Neolithic period between 4000 and 2000 BC. It consists of hexagonal pillars made by the cooling lava of volcanic eruptions. The heights of the pillars, or columns, vary according to how fast the lava cooled. The Irish mythology behind the natural wonder of The Giant's Causeway is that a giant named Finn McCool built it so he could reach Scotland to fight his Scottish rival, Benandonner.

The ancient Mayans used causeways called sacbeob to connect different parts of a city for the easiest possible access. The Mayan word sacbe means “white way.” The Mayan style of causeway was usually topped with white stone. The white stone topped Mayan causeway in Nakbe, Guatemala, dates back to the Early Formation era of 1400 BC.

West Lake, in China's Zhejiang province, is sectioned by several different causeways. King Fahd Causeway in Saudi Arabia serves as a connector bridge. It joins Bahrain Island to the Kingdom of Saudi Arabia. The Johor is another one of the world's connector type of causeways. It joins Singapore with Peninsular Malaysia.

The Johor is also one of the many causeways that charge motorists toll fees. Toll fees are used by government transportation departments to help offset the cost of building new bridges or roadways. Companies that specialize in the construction of causeways for irrigation purposes first need the site looked at by experts in water supply systems. In some areas, environmental protection inspectors may be required to approve the application to build causeways. For instance, causeways may change the water flow and movement of sediment that may affect the growth of water life such as reefs and seagrass.

The Lake Pontchartrain Causeway in Southern Louisiana in the United States is one of the toll types of causeways. It's estimated that at least 42,000 cars travel the Pontchartrain on an average weekday. The Pontchartrain is often said to have the world's longest bridge, but it may actually be second to Thailand's Bang Na Expressway. Which causeway of the two is really the longest is often disputed.