A small but mighty guardian

It’s Lighthouse Day in the United States, so let’s stroll over to Spring Point Ledge Light on the breakwater next to Southern Maine Community College 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. In the US, caisson lighthouses became popularly known as ‘bug lights,’ 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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