Sterling Hill Mining Museum - Credit: Wikimedia Commons
The Sterling Hill Mine, now known as the Sterling Hill Mining Museum, is a former zinc mine in Ogdensburg, Sussex County, New Jersey, United States. It was the last working underground mine in New Jersey. It closed in 1986, and became a museum in 1989. Along with the nearby Franklin Mine, it is known for its variety of minerals, especially the fluorescent varieties. It was added to the National Register of Historic Places in 1991. Read more on Wikipedia
Source: en.wikipedia.org