Brunette Girl With Blue Eyes Posing On Rocks In A Small Cave

Caves are found throughout the world, but only a portion of them have been explored and documented by cavers. The distribution of documented cave systems is widely skewed toward countries where caving has been popular for many years (such as France, Italy, Australia, the UK, the United States, and so on.). As a result, explored caves are found widely in Europe, Asia, North America, and Oceania but are sparse in South America, Africa, and Antarctica. This is a great generalization, as large expanses of North America and Asia contain no documented caves, whereas areas such as the Madagascar dry deciduous forests and parts of Brazil contain many documented caves. As the world’s expanses of soluble bedrock are researched by cavers, the distribution of documented caves is likely to shift. For example, China, despite containing around half the world's exposed limestone - more than 1,000,000 square kilometres (390,000 sq mi) - has relatively few documented caves.
Records and superlatives
• The cave system with the greatest total length of surveyed passage is Mammoth Cave (Kentucky, USA) at 628 kilometres (390 mi) in length. This record is unlikely to be surpassed in the near future, as the next most extensive known cave is Jewel Cave near Custer, South Dakota, at 242 kilometres (150 mi).