Wyandotte Cave (GM-40)
Old Cave, the part known before 1850, consists of a passageway extending from the cave entrance to the Pillar of the Constitution, a stalacto-stalagmite about 25 feet in diameter and 35 feet high. New Cave, containing the larger part of the cavern, was discovered in 1850. Subsequent exploration revealed many points of interest, such as Monument Mountain, a huge mass of breakdown about 105 feet high and said to be the largest feature of its kind in the United States.
Our Hoosier State Beneath Us: Geomorphology