Spring Point Ledge Light

Welcome to Spring Point Ledge Light in South Portland, Maine. Lighthouse enthusiasts will recognise this as a caisson-style light station, meaning it’s a lighthouse built on top of a water-tight chamber called a caisson. Caisson lighthouses became popularly known as “bug lights” in the United States, and after the invention of the internal combustion engine, many people started calling them “sparkplug lighthouses”. Most caisson lighthouses are offshore or on dangerously exposed sites, but this is the only sparkplug lighthouse in the country that visitors can walk to.
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