It's the largest freshwater lake on Long Island, but it has a deadly and mysterious past.

New 12 Long Island's Rich Barrabi took a look at the legends that surround Lake Ronkonkoma.

One of the most popular legends is that of the Lady of the Lake. As the legend goes, back in the 1600s a Setauket Indian princess named Princess Tongawanga was left heartbroken after her father refused to let her be with the love of her life - a white European settler. Distraught, she took her canoe to the middle of Lake Ronkonkoma, plunged a knife into her heart and died. Some say her spirit lives in the lake, and every year she takes one white male victim.

Lake Ronkonkoma historian Dale Spencer says that from 1893 until today, 166 men have died on the lake.

The tales also speak of a bottomless lake that swallows its victims and deposits them into the Long Island Sound. Professional diver Bill Pfeiffer has mapped the entire bottom of the lake, and says that it does have a bottom. At one point its floor is more than 60 feet deep. Pfeiffer says that the lake doesn't empty out into the Long Island Sound.

As for the Lady of the Lake, Pfeiffer says that a few years ago, he was diving with a female marine biologist, who swears she descended into the black hole, saw a bright blue light and was embraced by long black hair for 20 to 30 seconds, before she was let go.

Despite the stories, Spencer says there is no verifiable evidence to suggest that the princess existed.