Precisely what area is encompassed in this hypothetical "mystery triangle" is not clear, but it is purportedly centered on Glastenbury Mountain and would include some or most of the area of the towns immediately surrounding it, especially Bennington, Woodford, Shaftsbury, and Somerset. Glastenbury and its neighboring township Somerset were both once moderately thriving logging and industrial towns, but began declining toward the late 19th century, and are now essentially ghost towns, unincorporated by an act of the Vermont General Assembly in 1937.