Landforms and terrestrial features

Attu Island

Attu Island (Atux̂), westernmost of Alaska's Aleutians: 346 sq mi, uninhabited since 2010. Site of the June 1942 Japanese occupation and the May 1943 Battle of Attu, the only WWII land battle on North American soil.

Auckland Island

Auckland Island (Maukahuka), largest island of the Auckland Islands, an uninhabited New Zealand subantarctic World Heritage archipelago 465 km south of Bluff; volcanic, 46,000 ha, home to endemic birds, sea lions, and a planned pig, cat, and mouse eradication.

Auckland Islands

Auckland Islands (Maungahuka, Mōtū Maha): largest of New Zealand's five subantarctic island groups, 465 km south of Bluff, 57,000 ha, volcanic and glaciated. World Heritage 1998; Polynesian, sealing, Enderby colony, shipwreck, and coast-watcher history; pigs, cats, mice remain on main island.

Auguste Island

Auguste Island is a small flat-topped island in the Palmer Archipelago, Antarctica, charted by the Belgian Antarctic Expedition in 1898 and named by Adrien de Gerlache for his father.

Aurora Basin

Aurora Basin (Aurora Subglacial Basin): large marine-based subglacial basin in Wilkes Land, East Antarctica, named for the AAE ship Aurora; its outlet glaciers, led by Totten, dominate East Antarctic ice loss. Distinct from the small Halmahera Sea undersea Aurora Basin adopted by GEBCO in 2023.

Australian Speleological Federation

Australian Speleological Federation (ASF), founded 1956, is Australia's national caving body: an ACNC-registered environmental organisation of 26 clubs and 950+ members, representing Australia on the International Union of Speleology and publishing caving codes, Caves Australia, and Helictite.

Austvågøya

Austvågøya, Norway's ninth largest island (530 km²) in Nordland county, lies at the Lofoten–Vesterålen boundary, split between Hadsel and Vågan. It holds Svolvær, Kabelvåg, and the medieval town of Vágar.

Avachinsky

Avachinsky (Avacha volcano), an active Kamchatka stratovolcano near Petropavlovsk-Kamchatsky, 2,717 m, last erupted 2001; over 150 Holocene explosive eruptions, some VEI 5, after a 30,000–40,000-year-old sector collapse.

Awaji Shima

Awaji Shima, or Awaji Island, is an island in Hyogo Prefecture, Japan, between Honshu and Shikoku with about 127,000 residents, crossed by the Akashi Kaikyo Bridge.

Axel Heiberg Island

Axel Heiberg Island (Umingmat Nunaat), a 35,180 km² uninhabited island in Nunavut's Sverdrup Islands, known for its Müller and Steacie ice caps, 40-million-year-old mummified fossil forest, McGill Arctic Research Station, and thick Sverdrup Basin geology.

Ayelu

Ayelu (Ayalu) is a 2,145 m vegetated rhyolitic stratovolcano in southern Afar, Ethiopia, paired with Abida/Adwa and part of the Adda'do Magmatic Segment, with only an uncertain 1928 eruption on record.

Ayon Island

Ayon Island (Ostrov Ayon), a roughly 2,000 km² low tundra island in the East Siberian Sea at the entrance to Chaunskaya Bay, Chukotka, Russia; village of Ayon, reindeer-herding history, 120 km winter ice road to Pevek.

Aýrybaba

Aýrybaba (Ayri-Baba) is the highest mountain in Turkmenistan, about 3,139 m, in the Koytendag or Kugitang range of the Pamir-Alay on the Uzbek border; a sacred two-headed summit with annual Flag Day climbs by the Agama club.

Azov Upland

Azov Upland (Приазовська височина), plateau in southeastern Ukraine on the Azov Crystalline Massif of the Ukrainian Shield; watershed plain 200–250 m, highest point Belmak-Mohyla (324–327 m), mohyly residual hills, chernozem steppe mostly cultivated.

Azuero Peninsula

Azuero Peninsula (Península de Azuero), Panama's Pacific cattle-ranching heartland in Herrera, Los Santos, and Veraguas; heavily deforested tropical dry forest, Azuero spider monkey habitat, active restoration programs, and Campanian-Eocene forearc geology with the Cerro Quema gold deposit.

Azufral

Azufral, also known as Azufral de Túquerres and formerly called Chaitán, is an active stratovolcano in Nariño department, southwestern Colombia, rising to 4,070 m (13,353 ft).

Azul, Cerro (volcano, Chile)

Cerro Azul is a 3,788 m stratovolcano at the southern end of the Descabezado Grande system in central Chile, whose Quizapu vent produced one of Chile's largest eruptions in 1932.

Azure Window

The Azure Window (It-Tieqa tad-Dwejra) was a 28 m limestone sea arch at Dwejra, Gozo, Malta, famous from Game of Thrones, which collapsed in a storm on 8 March 2017 and is now a dive site.

Babine

Babine names a lake, river, and mountain range in central British Columbia, from the French "babine" (lip) applied by fur-trade voyageurs to Carrier people wearing labrets. Babine Lake is Canada's largest sockeye nursery, producing up to 90% of Skeena sockeye.

Babuyan Island

Babuyan Island: northernmost main island of the Babuyan Islands, Cagayan, Philippines; 73.53 km2 volcanic island with Babuyan Claro and Smith volcanoes, last erupting 1924, home of the Ibatan people.

Baby Island

Baby Island, also known as Hackney Island, is a small 600-foot-long islet in Saratoga Passage, Island County, Washington, at the mouth of Holmes Harbor near Whidbey Island.

Bach Ice Shelf

Bach Ice Shelf, an ice shelf in the southern embayment of Alexander Island, west Antarctic Peninsula, named after Johann Sebastian Bach. Area about 4,536 km² in 2010, sustained retreat, decoupling from the Monteverdi Peninsula pinning point, and resumed meltwater export.

Oct 22, 2026

Badami Cave 3

Badami Cave 3 is a rock-cut Vaishnava temple at Badami, Karnataka, dedicated by Chalukya king Mangalesha in 578/579 CE and considered the earliest dated Hindu temple in the Deccan.

Badami cave temples

Badami cave temples: four 6th-7th century rock-cut sanctuaries at Vatapi, Early Chalukya capital in Karnataka; three Hindu caves (Shiva, Vishnu) and one Jain cave of Mahavira, carved in red sandstone.

Badwater Basin

Badwater Basin, in Death Valley National Park, California, is the lowest point in North America at 282 ft (86 m) below sea level, a ~200-square-mile salt flat of sodium chloride formed in a subsiding pull-apart basin, site of ancient Lake Manly and the 2023–2024 temporary lake.

Baffin Island

Baffin Island (Qikiqtaaluk), Nunavut, Canada: largest Canadian and fifth-largest world island, 507,451 km², home to Iqaluit, the Barnes and Penny ice caps, Auyuittuq National Park, and the Mary River iron mine.

Bagana

Bagana is an active andesitic lava cone (stratovolcano) on Bougainville Island, Papua New Guinea, 1,855 m high, erupting since at least 1842, with near-continuous lava effusion since 2000 and extreme SO2 degassing.

Oct 22, 2026

Bagh Caves

The Bagh Caves are nine rock-cut Buddhist caves in Madhya Pradesh, India, excavated around the 4th to 6th century CE and known for Gupta-period murals.

Bahama Islands

Bahama Islands: low-lying archipelago of 700+ limestone islands and cays southeast of Florida, also called the Lucayas, sitting on the Great and Little Bahama Banks carbonate platforms; highest point Mount Alvernia, 63 m, on Cat Island; independent Commonwealth country since 1973.