Indian Caverns

Indian Caverns is a show cave in Spruce Creek, Pennsylvania, United States. It is a horizontal karst cave of Ordovician Nealmont/Benner limestone, estimated to be about 500,000 years old. It is the second-largest cave in Pennsylvania and the largest limestone cave. Indian Caverns consists of two sections, originally separated by a 14-foot wall: the "Historic Cave" and the "Giant's Hall". The "historic" part of the cave is generally low-ceilinged and closer to the surface (as shallow as 15 ft) with a couple of wide rooms and extensive speleothem formation. The Giant's Hall area consists of several large passageways, up to 60 feet high, but with fewer speleothems - though it does include the largest sheet of flowstone in the northeast and a substantial rimstone pool. The lowest point of the cave is approximately 140 feet beneath the surface and the cave temperature is a constant 56 degrees Fahrenheit (13 degrees Celsius).

Artifacts found in the cave indicate that it was inhabited as long ago as 8000 BCE. The earliest tribe known to have used the cave were the Susquehannocks, circa 1600 CE. It was later used by Algonkian (including Lenni Lenape) and Iroquois (probably Mohawk) tribes through the early eighteenth century. Examples of the artifacts are on display in the cave and include arrow and spearheads, tobacco pipes, tomahawks, punches, banner stones, a bone flute, and pottery shards. They also include a rare effigy of the Algonkian guardian spirit, Mesingw.

One room, the "Grotto of the Wah-Wah-Taysee", features a phosphorescent mineral deposit in the ceiling and walls. It was originally thought to be radium, but has since been identified as zinc sulfide reacting with calcite in the limestone. The cave also contains a "musical rock", which resounds with a bell-like tone when struck.

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