The Riverbluff Cave is a paleontological site discovered in the United States, near Springfield, Missouri. The entrance is filled with stalactites, stalagmites and columns. The cave is about 830,000 years old (making it the oldest known fossil cave site in the US) and 610 m long, featuring the Pleistocene fossils, notably of the short-faced bear (Artcodus simus) the largest bear species on the Earth (about 6 feet tall at the shoulder and weighing 1,400 pounds).^[2]

• http://en.wikipedia.org/wiki/Riverbluff Cave