Along with high tides and howling winds, Hurricane Sandy delivered a Halloween mystery: a skeleton beneath an uprooted tree.

A Connecticut resident found the skeleton beneath the toppled “Lincoln Oak,” a 103-year-old historic tree on the New Haven Green that was a casualty of the storm. The police and a medical examiner soon arrived on the scene and confirmed that the bones did not belong to any recent murder victim, Raw Story explains. Rather, they speak to the Green’s history as a cemetery. The park was used as a grave site as far back as the 1650s, often providing the final resting place for small pox victims.

In an 1897 book, Historical Sketches of New Haven, author Ellen Strong Bartlett wrote, “Sometimes, at the dead of night, apart from the others, the victims of smallpox were fearfully hidden here. The ground was filled with graves between the Church and College Street; sixteen bodies having been found within sixteen square feet.”

In 1821, townspeople moved the headstones to a new location, but they left many of the skeletons behind. Today, historians estimate that more than 1,000 bodies slumber beneath frolicking children, dog walkers and concert-goers on the New Haven Green.

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