Blue Spring Cave is a cave located in White County, Tennessee, on the north side of Blue Spring Cove. Blue Spring Cave is Tennessee's longest cave and the 9th longest cave in the United States. Blue Spring Cave had an explored length of only 500 feet as recently as 1989. In that year a group of cave explorers enlarged a blowing crack at the rear of the cave that dropped into a large passage which they named Johnson Avenue, in honor of the owner of the property on which the cave's entrance is located.