The Bennington Triangle is a window area located in Vermont, centered around Glastenbury Mountain and the ghost town of Fayville. According to local legend, the Indians of the region avoided Glastenbury Mountain because there was supposed to be a mysterious stone on it that would swallow people up.
Of course, that didn't stop settlers from building a town on it, but that didn't work out so well. Fayville went into decline in the 19th century, there was the usual “cursed town” descent into madness and murder, and eventually the town was completely abandoned. Now it's just a bunch of old stone foundations scattered around the forest on Glastenbury Mountain.
A number of people went missing in the area in the 1940s, and no trace was ever found of most of them- perhaps they were swallowed up by the legendary stone? Finally, there's also supposed to be a local monster of some kind that roams around in the forest.
Glastonbury Hill in England is supposed to be a gateway to Avalon, and “Fayville” can be read as “fairy village”- but I think both of these similarities are merely interesting coincidences. If you ever decide to go up Glastenbury Mountain to explore the ruins of Fayville, just be careful not to fall into one of the old foundation pits- or else you could be the next person to disappear in the Bennington Triangle! Also, if you happen to see a mysterious glowing stone opening up into a gateway into another reality, I'm not going to tell you not to go into it but you should probably bear in mind that no one else has ever come back from that place before...