This is what the website says. "Built in 1957 the light was lit the first time in May 1958." I couldn't find a specific timeframe.
It was built in September of 1957. It was a continuous pour utilizing a slip jack form that rose eight to twelve inches an hour. The pour started on a Monday morning and they reached the top one week later on a Monday afternoon.
They used special construction techniques that allowed the entire light house to be built in one pour of concrete. So how ever long that took.
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