#1: Grotto Azzurra, Italy

amazing cavesGrotto Azzurra or Blue Grotto is one of Capri island’s greatest attractions. It’s a sapphire-hued sea cave only accessible during low tide as the cave’s entrance is a mere metre high and two metres wide. Though not as long or as deep as many of the other caves listed here, its sheer beauty would make it worth the trip. Tours of the Blue Grotto are provided by local operators, two of which, Motoscafisti di Capri and Laser Capri, offer round-trip boat excursions from €15 (US$18). It can get a bit crowded, especially during the summer peak season. If you’d rather avoid the crowds, visit during off-peak  seasons.

#2: Skocjan Cave, Slovenia

This impressive Slovenian cave system was inscribed a UNESCO World Heritage Site in 1986.      Containing evidence of human inhabitation as far back as 10,000 years, the Skocjan Caves are a must-see attraction for anyone travelling through Slovenia. Some of the caves’ highlights include one of the world’s largest known underground canyons; the Big Collapse Doline (or sinkhole) and the Little Collapse Doline, where the entrance to the caves can be found; the Rimstone Pools and even some underground waterfalls.

#3: Waitomo Glowworm Cave, New Zealand

amazing cavesFamous for being home to a species of glowworm endemic to New Zealand, the Waitomo Glowworm Caves of North Island offer visitors a jaw-dropping encounter with one of Mother Nature’s true      wonders – the shimmering bioluminescence of these special insects.

A number of cave tours are available, with the Waitomo Glowworm Cave Tour (NZ$50 or US$36)    taking spelunkers through the renowned Glowworm Grotto. In addition to touring the vast cave      systems at Waitomo, several other adventure activities are on offer, including rock climbing,        blackwater rafting and abseiling.

#4: Sterkfontein Caves, South Africa

Located about a 45-minute drive from Johannesburg, the Sterkfontein Caves are notable, particularly in the discipline of paleo-anthropology. Not only are the caves beautiful and boast an impressive     underwater lake, but due to the vast number of fossils recovered in the area, the region in which the caves are located has been dubbed the Cradle of Humankind, and has been granted UNESCO World Heritage status.

The caves are open to the public every day from 9am to 5pm with tours costing R165 (US$13) for adults. If you have the time and inclination, go for a combo ticket (R190) which gives you access to both the caves and the incredible Maropeng, the Cradle of Humankind’s award-winning visitors’    centre and interactive museum.

#5: Cango Caves, South Africa

amazing cavesAnother impressive South African cave system, the Cango Caves outside of Oudtshoorn in the    Western Cape are a real natural phenomenon. Famed for their spectacular, almost otherworldly speleothems (cave formations), the caves attract visitors from all over the world. Two tour options are available for visitors: the 60-minute Heritage Tour (R110) and the 90-minute Adventure Tour (R165) respectively.

To preserve the cave’s integrity, limited numbers of tourists are permitted each day, so booking in    advance is essential. Additionally, due to the cramped and often tight spaces within the cave systems, pregnant women and those suffering from claustrophobia, high blood pressure or muscular ailments are advised not to visit.

#6: Mammoth Cave, Kentucky, USA

amazing cavesAs far as record-breaking caves go, Mammoth Cave in Kentucky is very special. To date, over 650km of passages have been identified and surveyed, leaving the Kentucky cave with the title of the world’s longest known cave system, almost double the length of the second longest, Sac Actun in Mexico. Some of the best sights include Fat Man’s Misery, a snaking and extremely narrow section of passageways; an abundance of unique cave-dwelling creatures often found nowhere else on earth; Frozen Niagara, a giant curtain of stone resembling a waterfall and the cave formations in the Drapery Room.

#7: Puerto Princesa Subterranean River National Park, Philippines

amazing cavesListed as one of the New 7 Wonders of Nature, the 8.2-km Puerto Princesa Subterranean River is an underground waterway that boasts impressive cave formations, underground waterfalls and an abundance of wildlife, including several mammalian and reptilian species. To really enjoy the marvel that is Puerto Princesa’s famous cave system, a boat tour through the underground river and caves would be best. An official tour of the river and cave system costs 2,200 pesos (US$43) for adults and includes transfers, guides, entry fees and even a buffet lunch.

#8: Sơn Đoòng Cave, Vietnam

amazing cavesHousing the world’s largest known cave passage, Sơn Đoòng Cave in the Quang Bình province of Vietnam was discovered by a local in 1991. The river that flows through the cave system created a cavernous passage so large, it can house an entire Boeing 747. The first tourist groups began visiting the cave in August 2013.

Tourists seeking to explore the cave require permits, of which only 800 are made available for a limited period from February through August each year, and through a sole tour operator, Oxalis Adventure Tours. Bear in mind that the Sơn Đoòng Expedition offered by Oxalis is a strenuous, multi-day hiking and camping tour that’s more suitable for healthy and fit individuals.

#9: Fingal’s Cave, Scotland

The uninhabited Staffa island, part of Scotland’s Inner Hebrides archipelago, may have passed under most travellers’ radar were it not for the poetically named Fingal’s Cave, a mysterious sea cave made famous by certain epic natural features. The first notable feature of this remote Scottish cave is its  natural acoustics, producing eerie sounds and echoes. Then there is the series of hexagonal basalt columns forming the entirety of the cave’s interior. A natural phenomenon caused by the rapid cooling off of lava flow, the basalt columns are similar to those found at the Giant’s Causeway in Ireland and the cave’s biggest claim to fame. In fact, legend holds that it’s the same giant (named Fion or Finn)  responsible for the causeway in Ireland to whom the Scottish cave’s formation can be attributed.

Sign up with a local operator such as Staffa Tours to get to and from Fingal’s Cave during its open season from April through September.

#10: Eisriesenwelt, Austria

amazing cavesJourney 40km south from Salzburg and you’ll discover Eisriesenwelt (German for ‘world of the ice    giants’), a cave system that is part of the Austrian Alps. Stretching through some 42km of icy Alpine caverns and tunnels, Eisriesenwelt is the largest ice cave on earth. Visitors are only permitted to enter the cave between May and October, with various touring options available. A regular adult ticket      offering both cable car ride and cave visit will cost €24. Some of the things to look out for include Posselt Hall and Tower (a large room and stalactite named after the first person to discover the cave); the Great Ice Embankment (the area with the biggest ice formation) and Frigga’s Veil, a fascinating  formation of stalactites.

Images:123rf.com, Eisriesenwelt facebook, Waitomo Glowworm Caves Facebook, Instagram, Cango Caves Facebook, Mammoth Cave National Park Facebook, Puerto Princesa Unederground River Facebook, Song Doong Cave Facebook.

This story first appeared on www.silverkris.com

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