Do not use dietary supplements that contain iodine in the place of KI (potassium iodide). They can be harmful and non-efficacious. Only use products that have been approved by the U.S. Food and Drug Administration (FDA).
Mammoth Cave, the world's longest known cave system. The following is a list of the world's 10 longest caves per length of documented passageways. Many passageways are still being discovered; this list is based on the latest verifiable data.he highest concentrations of long caves in the world are found in the Pennyrile of Southern Kentucky, USA, in the Black Hills of South Dakota, USA, and in the Yucatan YucatÃ¡n, Peninsula. mexico
CAVES, LAKES & CORVETTES. If youâre looking for adventure, thereâs no better place to find one than Kentuckyâs Caves, Lakes & Corvettes Region. Mammoth Cave National Park, home of the worldâs longest cave system at 400 miles explored so far, celebrates 200 years of cave tours in 2016. It has been a national park for 75 years and has been honored by UNESCO as one of only 23 World Heritage Sites in the United States.