Top Ten Longest Caves in The World

A cave is deep space in the earth or water where a human being can enter for exploration. The cave may vary according to its size and formation. Speleology is the science of caves exploration and caves studying. Here is the list of top ten 10 world’s biggest caves with their features and length.

	Mammoth cave system is the largest or longest natural cave system in the world as well as in North America or USA. Situated in  Kentucky, USA, this longest cave having 567 km of length. It is centered around the Green River, with a tributary and with 145 miles of passageways.
	Optimisticeskaja cave is a gypsum cave located near the village of korolivka in Ukraine. By some sources it is having about 133 miles of surveyed passageways. This is the second largest or longest cave by area in the world. Also it is regarded as the biggest or largest cave in Europe or EU.
	Jewel Cave it is the third longest cave in the world, with 108 miles of mapped passageways. It is located in South Dakota’s Black Hills (USA). Jewel cave is open year round. There are some surface trails, while reservations are not required, they are recommended during the summer seasons.
	Holloch cave is a 166 km long situated between the river Muota and the area of Pragelpass in the valley of Muotha in Switzerland. It is also popular for having a depth of 939m. It was the first cave in the world whose explored length reached 100km.  It is the biggest  cave of Switzerland and the second longest of Europe.
	Lechuguilla Cave is the fifth longest or largest cave with 161 km length. It is located in New Mexico (USA) and is the most famous for its unusual geology, rare formations and pristine condition. Cavers are greeted by large amount of gypsum and lemon-yellow sulphur deposits in this natural cave.
	Siebenhengsteholen-system is the longest or biggest cave system of Switzerland, while sixth longest cave of the world with 140 km length. It is famous for its unusual greenery. It presents the most amazing natural scenery with its green routs and vegetation.
	Fisher Ridge Cave system was discovered in 1981. The central part of Ridge which contains the bulk of the mapped passages on three different levels. It is located in Kentucky (USA) and its length is about 126 km.
	Wind Cave is one of the world’s longest caves. It is located in South Dakota (USA). It is 126 kilometers long therefore it is regarded as the eigth longest or largest cave in the world and fifth longest in United States Of America.
	Ozernay it is a small shield volcano located in the southern part of Ukraine. It is most wonderful cave with 111 km length. The passage of this cave is full of amazing natural scenes. This cave is difficult to visit.
	Gua Air Jernih is tenth longest cave of the world. It is located in Malaysia and it is 109 kilometer long. This cave is the longest cave of Malaysia as well as Asia.