The last time there was any type of volcanic magma activity in this area was hundreds of millions of years ago, so you do not need to worry about any type of eruption any time soon.

About 420 million years ago, there was volcanic activity in New Jersey. More than a century ago a volcanic vent was discovered in Sussex County, known as Rutan Hill, or the Beemerville Volcano. Rutan Hill has no crater, and its eroded remains are approximately 1,500 feet in diameter.

While you cannot visit or explore Rutan Hill because it’s located on private property, but you can certainly hike see the hill from a distance.