Caisson lighthouse

A caisson lighthouse is a lighthouse whose superstructure rests on a concrete or metal caisson.

Caisson lighthouses were developed in the late nineteenth century as a cheaper, more efficient alternative to screwpile lighthouses; they could better withstand harsh weather, and were not as fragile. Generally speaking, the house was made of cast iron, although some brick examples are known.

Most caisson lighthouses were built at fairly exposed stations, but a few exist closer to shore.

Wolf Trap Light and Baltimore Light, both in the Chesapeake Bay, are examples of caisson lighthouses.

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