NR-1 Sinkhole NR-1 Sinkhole The NR-1 Sinkhole is a giant underwater sinkhole located in the Straits of Florida southwest of Key West, Florida. It is found at an approximate depth of of water at the foot of the Pourtales Escarpment, an area of Quaternary sediment. It was discovered in October 1994 during a survey conducted by the American submarine NR-1, a U.S. Navy nuclear research submarine, and is named for the submarine. It was first identified via side-scan sonar and near-bottom echo sounder data, prompting a second survey in May 1995 to confirm the finding. Discovery of the NR-1 Sinkhole prompted scientific
Cave Without a Name human contact with the cave began only in the early 20th century, when a small farm animal became trapped in the small external opening of the cave, known as a sinkhole. The cave went largely unnoticed again until the 1920s during the era of Prohibition when a small moonshine distillery was installed in the uppermost cavern. It again fell into obscurity until three local farm children rediscovered the sinkhole in 1935. These children are believed to be the first who actually entered the main chambers of the cave. After the rediscovery, Jim Horn, the original owner of the property decided