For a long time, I have made fun of Allentown as being full of people named Allen where brothers, sisters, and cousins sleep with each other, but the incest capital of New York is actually Oriskany Falls N.Y.

From the website Weird are us-

The Incest Butterflies of Oriskany Falls
Welcome to Oriskany Falls—the incest capital of the world—or so the stories go.

A popular legend at Colgate University says that Oriskany Falls, a tiny quaint village near the university and home to less than 800 people, is actually the home of a secret cult, whose members are all united by familial bonds and the practice of incest. The cult is so well known on campus because its members supposedly hate the nearby university and its students and faculty. Students warn each other not to set foot in the town, lest they face the wrath of the cult’s members, who do not want to be gawked at by the curious prying eyes of anyone.