Mass Grave of the St. Patrick's Day Parade Horror

Valhalla, New York

The Windsor Hotel burst into flames in 1899 just as New York City's St. Patrick's Day Parade passed in front of it, probably when someone leaned out a window to watch, amid billowing curtains, with a lit cigarette or cigar.

The building was reduced to a smoldering ruin, and 86 people were thought to have died -- either burned, choked, or crushed when they leapt to their doom -- including firefighters who ran into the building from the parade wearing only their dress uniforms. 31 bodies were never identified and were buried in an unmarked mass grave in Kensico Cemetery, whose Board of Directors had held their meetings at the hotel.

The anonymous dead were forgotten for over 115 years, until a black tombstone was unveiled on the spot on October 9, 2014, as part of National Fallen Firefighters Memorial Weekend. It features an engraved reproduction of an old newspaper photograph taken at the scene of the fire.