The 30 Most Incredible Caves and Karst Landscapes

The world underground and the strange stone country it makes above: chambers and underground rivers, limestone towers and hidden valleys. These are the atlas’s caves and karst landscapes.

Benagil Sea Cave

Benagil, Algarve, southern Portugal

A domed sea cave on the Algarve coast whose vaulted limestone roof is pierced by a great circular skylight — an 'oculus' that pours a column of sunlight onto a hidden beach reachable only from the water.

Cave Europe

Eisriesenwelt

Werfen, Salzburg, Austria

The world's largest ice cave, above Werfen in Salzburg. Open daily 1 May–31 Oct 2026 for 70-minute guided tours: 700 steps up through the ice by lamplight, below 0 °C even in summer. A cable car and two 20-minute walks lead to the 1,641 m entrance. No photos inside.

Cave Europe

El Nido & the Bacuit Archipelago

El Nido, Palawan, Philippines

A bay scattered with dozens of jagged limestone islands, hidden lagoons reached through narrow rock gaps, white beaches, and clear turquoise water — one of the most spectacular karst seascapes in the world.

Karst landscape Southeast Asia

Gunung Mulu

Sarawak, Borneo, Malaysia

A Bornean rainforest hiding some of the world's greatest caves — including the largest cave chamber on Earth — plus razor-sharp limestone pinnacles rising from the jungle canopy.

Cave Southeast Asia

Hạ Long Bay

Gulf of Tonkin, northeastern Vietnam

A jade-green sea studded with nearly 2,000 limestone karst islands and pillars rising sheer from the water — caves, hidden lagoons, and floating villages in one of the world's most beautiful seascapes.

Karst landscape Southeast Asia

Marble Caves

General Carrera Lake, Aysén, Chile

Swirling caverns of polished marble at the water's edge of a remote Patagonian lake — their blue-and-white walls glowing turquoise with the reflected light of the glacier-fed water.

Cave Latin America

Phong Nha-Kẻ Bàng

Quảng Bình Province, Vietnam

An ancient limestone landscape riddled with the world's greatest cave systems — including Sơn Đoòng, the largest cave passage on Earth, big enough to hold its own jungle, river, and clouds.

Cave Southeast Asia

Puerto Princesa Subterranean River

Puerto Princesa, Palawan, Philippines

One of the world's longest navigable underground rivers, winding 8.2 km through a vast limestone cave system beneath a karst mountain range before emptying directly into the West Philippine Sea.

Cave Southeast Asia

The Yucatán Cenotes

Yucatán Peninsula, Mexico

Thousands of natural sinkholes opening into a hidden world of crystal-clear groundwater and flooded caves beneath the Yucatán — the peninsula's only natural fresh water and among the most beautiful swimming holes on Earth.

Cave North America

Tsingy de Bemaraha

Melaky, western Madagascar

A vast 'forest of stone' — a labyrinth of razor-sharp limestone pinnacles rising in grey blades from the Madagascar wilderness, hiding canyons, caves, and creatures found nowhere else.

Karst landscape Africa

Blue Cave of Biševo

Biševo island, off Vis, Dalmatia, Croatia

A sea cave on the tiny island of Biševo that fills with an unearthly blue light around midday, when sunlight enters through a submerged opening and glows up through the water onto the cavern's walls.

Cave Europe

Callao Cave

Peñablanca, Cagayan, Northern Luzon

A vast limestone cave of seven great chambers lit by natural skylights — and the site where the ancient human species Homo luzonensis was discovered, deep in the karst of the Cagayan Valley.

Cave Southeast Asia

Guilin & the Li River Karst

Guangxi, southern China

The landscape of Chinese scroll paintings brought to life — thousands of rounded limestone peaks rising from green plains and the winding Li River, mirrored in still water beneath drifting mist.

Karst landscape East Asia

Hpa-An Karst

Kayin State, southeastern Myanmar

A landscape of sheer limestone karst mountains rising straight from emerald rice paddies in southeastern Myanmar, riddled with vast caves full of Buddha images and roosting bats.

Karst landscape Southeast Asia

Kong Lor Cave

Khammouane Province, central Laos

A river cave that tunnels for over seven kilometres straight through a limestone mountain — navigated by longtail boat through pitch darkness, from one green valley to another.

Cave Southeast Asia

Los Haitises

Samaná Bay, Hato Mayor, Monte Plata and Samaná provinces, Dominican Republic

A limestone plateau eaten into hundreds of conical hills of almost identical height — and where it meets Samaná Bay, the hilltops continue offshore as forested islets standing in the water.

Karst landscape Latin America

Mammoth Cave

Kentucky, USA

The longest cave system known on Earth — over 685 kilometres of mapped passages winding beneath the Kentucky hills, with new miles still being discovered.

Cave North America

Masungi Georeserve

Baras, Rizal, Philippines

A dramatic limestone karst landscape barely 90 minutes from Manila, reborn as a conservation project — jagged rock formations, rope courses, and hanging viewpoints woven through a rainforest being restored tree by tree.

Karst landscape Southeast Asia

Melissani Cave

Karavomylos, Kefalonia, Ionian Islands, Greece

An underground lake on the Ionian island of Kefalonia, roofed by a collapsed cavern that lets a shaft of midday sun ignite the brackish water in an unearthly electric blue.

Cave Europe

Phang Nga Bay

Andaman Sea, southern Thailand

A calm emerald bay between Phuket and Krabi studded with sheer limestone karst islands, sea caves, and hidden tidal lagoons reached by paddling through the rock.

Karst landscape Southeast Asia

Postojna Cave

Postojna, Inner Carniola, south-western Slovenia, off the A1 Ljubljana–Koper motorway

A 24-km karst cave system beneath Postojna, toured by a double-track underground railway first opened in 1872 — halls of stalagmites including the 16-m Skyscraper and the white Brilliant, and home of the blind cave salamander, the olm.

Cave Europe

Prometheus Cave

Imereti, near Kutaisi, western Georgia

A vast karst cave near Kutaisi, its huge chambers hung with stalactites and curtains of stone, explored on lit walkways and, in part, by boat along an underground river.

Cave Europe

Sagada

Sagada, Mountain Province, Cordillera, Philippines

A cool, pine-clad limestone highland in the heart of the Cordillera, where caves riddle the karst, waterfalls drop into rice terraces, and dawn breaks over a sea of clouds at Kiltepan.

Karst landscape Southeast Asia

Scărișoara Ice Cave

Apuseni Mountains, western Romania

A cave in Romania's Apuseni Mountains that holds one of the largest underground glaciers in the world — a block of ancient ice thousands of years old, deep beneath the forest.

Cave Europe

Škocjan Caves

Škocjan, near Divača, Karst region, south-western Slovenia

A UNESCO-listed river cave on Slovenia's Karst, where the Reka River drops into collapse dolines up to 165 m deep and roars through an underground canyon — about 6 km of passages and one of Europe's largest known cave chambers.

Cave Europe

Sơn Đoòng Cave

Phong Nha-Kẻ Bàng National Park, Quảng Bình Province, Vietnam

The largest known cave passage on Earth — a river-cut cavern in central Vietnam so vast that two collapsed skylights have let a jungle grow inside it.

Cave Southeast Asia

The Blue Grotto

Isle of Capri, Campania, Italy

A sea cave on the island of Capri where sunlight passing through an underwater opening fills the whole cavern with an unearthly, glowing electric-blue light.

Cave Europe

The Burren

County Clare, Ireland

A silver-grey moonscape of bare limestone pavement in County Clare — one of Europe's finest karst landscapes, where Arctic, alpine and Mediterranean wildflowers bloom together in the cracks of the naked rock.

Karst landscape Europe

Vang Vieng

Vientiane Province, central Laos

A dramatic landscape of sheer limestone karst peaks rising above the Nam Song river and green rice fields, riddled with caves and blue lagoons, in the hills north of Vientiane.

Karst landscape Southeast Asia

Viñales Valley

Sierra de los Órganos, Pinar del Río Province, western Cuba

Round-topped limestone towers standing up to 300 metres out of flat red tobacco fields in western Cuba — the same tower-karst process that built Ha Long Bay, on an island, and still farmed by hand.

Karst landscape North America