A causeway is a track, road or railway on the upper point of an embankment across "a low, or wet place, or piece of water".

One of the earliest known wooden causeways is the Sweet Track in the Somerset Levels, England, which dates from the Neolithic age.

Originally, the construction of a causeway used earth that had been trodden upon to compact and harden it as much as possible, one layer at a time, often by slaves or flocks of sheep.

modern chaussée),[3] from the late Latin via calciata, a road stamped firm with the feet (calcare, to tread).

In East Africa, the Husuni Kubwa (the "Great Fort"), situated outside the town of Kilwa, was an early 14th-century sultan's palace and emporium that contained causeways and platforms at the entrance of the Harbour made from blocks of reef and coral nearly a meter high.

[6] In Scotland, the skirmish known as Clense the Calsey, or Cleanse the Causeway, took place in the High Street of Edinburgh in 1520.

[7] In the 18th century, Dahomey lacked an effective navy hence it built causeways for naval purposes starting in 1774.

This may also be the primary purpose of a structure, the road providing a hardened crest for the dike, slowing erosion in the event of an overflow.

Constructed in waters up to 18 metres deep, the four barriers link five islands on the eastern side of the natural harbour at Scapa Flow.

The sea on both sides of the causeway then became shallower as a result of silting, and mangroves began to conquer the area.

Later, land reclamation took place on both sides of the road and the area has subsequently been named Cotai and become home to several casino complexes.

Causeways affect currents and may therefore be involved in beach erosion or changed deposition patterns; this effect has been a problem at the Hindenburgdamm in northern Germany.