3,546 articles
Sistema Dos Ojos
Sistema Dos Ojos, a flooded cave system near Tulum, Quintana Roo, Mexico, named for two eye-like cenotes. About 84 km long, it was connected to Sistema Sac Actun in January 2018 and absorbed as its Dos Ojos region; El Pit reaches 119 m.
Sistema Ox Bel Ha
Sistema Ox Bel Ha ("Three Paths of Water") is the world's longest underwater cave, a flooded karst system south of Tulum, Quintana Roo, Mexico, surveyed at 541,791 m by CINDAQ in 2025, explored since 1997, and second only to Mammoth Cave among all caves.
Sittanavasal Cave
Sittanavasal Cave (சித்தன்னவாசல்), called Arivar Koil, is a rock-cut Jain cave temple in Pudukkottai district, Tamil Nadu, India, celebrated for early medieval murals of the Jain Samavasarana, ranked after Ajanta.
Sivalik Hills
Sivalik Hills (Churia/Chure Hills), southernmost and lowest Himalayan range, about 1,700 km long through Pakistan, India, and Nepal, built of up to 6,000 m of Neogene Siwalik Group molasse and uplifted along the active Main Frontal Thrust.
Skalistyy Golets
Skalistyy Golets (Гора Скалистый Голец) is the name of two mountains in eastern Russia, including the 2,519 m highest point of the Kalar Range in Zabaykalsky Krai.
Skeleton Coast
Skeleton Coast: northern Atlantic shore of Namibia, about 500 km from the Ugab to the Kunene River, famed for Benguela Current fog, whale bones and shipwrecks such as the Eduard Bohlen and Zeila, largely within Skeleton Coast National Park.
Skellig Michael
Skellig Michael (Irish: Sceilg Mhichíl), also called Great Skellig, is a rocky island off County Kerry, Ireland, bearing an early medieval monastery inscribed by UNESCO in 1996.
Skerry
A skerry is a small, rocky island or reef, often visible only at low tide, found chiefly along the glaciated coasts of Scotland and Scandinavia.
Skjoldungen
Skjoldungen (Saqqisikuik) is a large uninhabited island in southeastern Greenland's Sermersooq municipality, named in 1829 by W.A. Graah, site of a settlement founded 1938 and abandoned 1964-65.
Skopelos
Skopelos (Σκόπελος) is the second largest island of Greece's Northern Sporades, covered in pine forest and known as the main filming location of Mamma Mia! (2008).
Skorpios
Skorpios (Σκορπιός) is a private Ionian island east of Lefkada, Greece, bought by Aristotle Onassis in 1962, site of his 1968 wedding to Jackie Kennedy, sold in 2013 for €117 million to the Rybolovlev family and now being turned into a resort.
Slessor Peak
Slessor Peak: mainly ice-covered 2,370 m peak at the SW end of Bruce Plateau, Graham Land, Antarctic Peninsula, near Gould Glacier; surveyed 1946-47 by FIDS and named for Robert S. Slessor. Distinct from Slessor Glacier in East Antarctica.
Smith Island
Smith Island, the southwesternmost island of the South Shetland Islands, Antarctica, named for explorer William Smith; 40 km long, rising to about 2,100 m at Mount Foster, with blueschist subduction-complex rocks metamorphosed 58-47 Ma.
Smith Peninsula (landform)
Smith Peninsula: an ice-covered, dog-legged peninsula on the Lassiter Coast, Palmer Land, Antarctica, between Keller and Nantucket Inlets, named for Walter "Smitty" Smith; also several peninsulas in Saskatchewan, Manitoba, and Nunavut.
Snaefell (volcano)
Snæfell is a Pleistocene central volcano in central-east Iceland near the northeastern edge of Vatnajökull, whose 1,833 m summit makes it Iceland's tallest subaerial volcano, with no known Holocene eruptions.
Snæfellsjökull
Snæfellsjökull is a 1,446 m glacier-capped stratovolcano on the western tip of Iceland's Snæfellsnes peninsula, centerpiece of Snæfellsjökull National Park (170 km²), with a 200 m ice-filled summit crater and about 16% of its Little Ice Age glacier area remaining.
Snæfellsnes
Snæfellsnes is a roughly 100-km peninsula in western Iceland, home to the 1,446 m ice-capped Snæfellsjökull stratovolcano, Snæfellsjökull National Park, and Iceland's first UNESCO Biosphere Reserve (2025).
Snake Island (Ukraine)
Snake Island (Zmiinyi, Leuke) is a 20-hectare Ukrainian island 37 km from the Danube delta, an ancient cult site of Achilles, subject of the 2009 ICJ Romania-Ukraine maritime case, and site of the famous February-June 2022 Russian occupation and withdrawal.
Snehaetten (Qertarsuaq/Disko)
Snehaetten, a 1765 m mountain peak on Qeqertaq Island (Qeqertarsuaq/Disko area), West Greenland; island high point with 1765 m prominence and 34.4 km isolation.
Snow Hill Island
Snow Hill Island (Isla Cerro Nevado) is an ice-covered island in the James Ross Archipelago, Weddell Sea, at 64°28'S 57°11'W, site of Nordenskjöld's 1902-03 winter station hut and the northernmost emperor penguin colony.
Snow Island
Snow Island (Isla Nevada) is an island in the South Shetland Islands, Antarctica, at 62°46'S 61°23'W, with President Head at its east end, ice-free President Head Peninsula, and a vanished chinstrap penguin colony.
Snow Tower
Snow Tower is a 6,572-foot summit in the Coast Range east of Juneau, Alaska (GNIS 1409827), first climbed June 8, 2015 by William Wacker and Mike Miller via the east face to east ridge.
Snowdon
Snowdon (Yr Wyddfa), 1,085 m, is Wales's highest mountain in Eryri National Park, with six walking routes, a rack-and-pinion railway opened in 1896, the Hafod Eryri summit centre, and over 600,000 annual visitors.
Snowshoe Peak
Snowshoe Peak is the highest summit of the Cabinet Mountains in northwestern Montana, rising to 8,738 feet and anchoring the Cabinet Mountains Wilderness in the Kootenai National Forest.
Snowy Mountain
Snowy Mountain (Alaska) is a pair of glaciated andesite-dacite stratovolcanoes 15 km NE of Mount Katmai in Katmai National Park, 2,161 m high, with a Holocene debris avalanche, lava dome, and fumarolic, GREEN/NORMAL status.
Snowy Mountains
The Snowy Mountains is the highest section of Australia's Great Dividing Range in southern New South Wales, known for containing Mount Kosciuszko, major rivers, and the Snowy Hydro-Electric Scheme.
Sob Gangri
Sob Gangri, also called Yuzhu Peak (玉珠峰), is a 6,178 m ultra-prominent peak in Qinghai, China, the highest of the eastern Kunlun Mountains, near the Qingzang Highway and a well-known introductory high-altitude climb.
Society Islands
The Society Islands (French: Archipel de la Société) are an archipelago of 14 islands in French Polynesia, divided into Windward and Leeward groups and containing Tahiti.
Socorro Island
Socorro Island (Isla Socorro), largest of Mexico's four Revillagigedo Islands, a volcanic island rising to Volcán Evermann (1,040 m) about 400 km southwest of Cabo San Lucas, with high plant and bird endemism, World Heritage status since 2016, and famous giant manta ray diving.
Sollipulli
Sollipulli, a 2,282 m stratovolcano in Chile's Andean Southern Volcanic Zone between Llaima and Villarrica, holds a 4-km glacier-filled caldera of non-explosive origin, a VEI 5 Alpehué Plinian eruption about 2,900 years ago, and a rapidly thinning caldera glacier.