252 Results

This entry contains a brief description of the topography of a country.


mostly rugged mountains; plains in north and southwest


mostly mountains and hills; small plains along coast


mostly high plateau and desert; Atlas Mountains in the far north and Hoggar Mountains in the south; narrow, discontinuous coastal plain

American Samoa

five volcanic islands with rugged peaks and limited coastal plains, two coral atolls (Rose Atoll, Swains Island)


rugged mountains dissected by narrow valleys


narrow coastal plain rises abruptly to vast interior plateau


flat and low-lying island of coral and limestone


about 99% thick continental ice sheet and 1% barren rock, with average elevations between 2,000 and 4,000 m; mountain ranges up to nearly 5,000 m; ice-free coastal areas include parts of southern Victoria Land, Wilkes Land, the Antarctic Peninsula area, and parts of Ross Island on McMurdo Sound; glaciers form ice shelves along about half of the coastline, and floating ice shelves constitute 11% of the area of the continent

Antigua and Barbuda

mostly low-lying limestone and coral islands, with some higher volcanic areas


rich plains of the Pampas in northern half, flat to rolling plateau of Patagonia in south, rugged Andes along western border


Armenian Highland with mountains; little forest land; fast flowing rivers; good soil in Aras River valley


flat with a few hills; scant vegetation

Ashmore and Cartier Islands

low with sand and coral


mostly low plateau with deserts; fertile plain in southeast


mostly mountains (Alps) in the west and south; mostly flat or gently sloping along the eastern and northern margins


large, flat Kur-Araz Ovaligi (Kura-Araks Lowland, much of it below sea level) with Great Caucasus Mountains to the north, Qarabag Yaylasi (Karabakh Upland) to the west; Baku lies on Abseron Yasaqligi (Apsheron Peninsula) that juts into Caspian Sea

Bahamas, The

long, flat coral formations with some low rounded hills


mostly low desert plain rising gently to low central escarpment


mostly flat alluvial plain; hilly in southeast


relatively flat; rises gently to central highland region


generally flat with much marshland


flat coastal plains in northwest, central rolling hills, rugged mountains of Ardennes Forest in southeast


flat, swampy coastal plain; low mountains in south


mostly flat to undulating plain; some hills and low mountains


low hills separated by fertile depressions


mostly mountainous with some fertile valleys and savanna


rugged Andes Mountains with a highland plateau (Altiplano), hills, lowland plains of the Amazon Basin

Bosnia and Herzegovina

mountains and valleys


predominantly flat to gently rolling tableland; Kalahari Desert in southwest

Bouvet Island

volcanic; coast is mostly inaccessible


mostly flat to rolling lowlands in north; some plains, hills, mountains, and narrow coastal belt

British Indian Ocean Territory

flat and low coral atolls (most areas do not exceed two m in elevation); sits atop the submarine volcanic Chagos-Laccadive Ridge

British Virgin Islands

coral islands relatively flat; volcanic islands steep, hilly


flat coastal plain rises to mountains in east; hilly lowland in west


mostly mountains with lowlands in north and southeast

Burkina Faso

mostly flat to dissected, undulating plains; hills in the west and southeast; occupies an extensive plateau with savanna that is grassy in the north and gradually gives way to sparse forests in the south


central lowlands ringed by steep, rugged highlands


hilly and mountainous, dropping to a plateau in east, some plains

Cabo Verde

steep, rugged, rocky, volcanic


mostly low, flat plains; mountains in southwest and north


diverse, with coastal plain in southwest, dissected plateau in center, mountains in west, plains in north


mostly plains with mountains in west, lowlands in southeast

Cayman Islands

low-lying limestone base surrounded by coral reefs

Central African Republic

vast, flat to rolling plateau; scattered hills in northeast and southwest


broad, arid plains in center, desert in north, mountains in northwest, lowlands in south


low coastal mountains, fertile central valley, rugged Andes in east


mostly mountains, high plateaus, deserts in west; plains, deltas, and hills in east

Christmas Island

steep cliffs along coast rise abruptly to central plateau

Cocos (Keeling) Islands

flat, low-lying coral atolls


flat coastal lowlands, central highlands, high Andes Mountains, eastern lowland plains (Llanos)


volcanic islands, interiors vary from steep mountains to low hills

Congo, Democratic Republic of the

vast central basin is a low-lying plateau; mountains in east

Congo, Republic of the

coastal plain, southern basin, central plateau, northern basin

Cook Islands

low coral atolls in north; volcanic, hilly islands in south

Coral Sea Islands

sand and coral reefs and islands (cays)

Costa Rica

coastal plains separated by rugged mountains including over 100 volcanic cones, of which several are major active volcanoes

Cote d'Ivoire

mostly flat to undulating plains; mountains in northwest


geographically diverse; flat plains along Hungarian border, low mountains and highlands near Adriatic coastline and islands


mostly flat to rolling plains, with rugged hills and mountains in the southeast


generally low, hilly terrain


central plain with mountains to north and south; scattered but significant plains along southern coast


Bohemia in the west consists of rolling plains, hills, and plateaus surrounded by low mountains; Moravia in the east consists of very hilly country


low and flat to gently rolling plains


coastal plain and plateau separated by central mountains


rugged mountains of volcanic origin

Dominican Republic

rugged highlands and mountains interspersed with fertile valleys


coastal plain (costa), inter-Andean central highlands (sierra), and flat to rolling eastern jungle (oriente)


vast desert plateau interrupted by Nile valley and delta

El Salvador

mostly mountains with narrow coastal belt and central plateau

Equatorial Guinea

coastal plains rise to interior hills; islands are volcanic


dominated by extension of Ethiopian north-south trending highlands, descending on the east to a coastal desert plain, on the northwest to hilly terrain and on the southwest to flat-to-rolling plains


marshy, lowlands; flat in the north, hilly in the south


mostly mountains and hills; some moderately sloping plains


high plateau with central mountain range divided by Great Rift Valley

European Union

fairly flat along Baltic and Atlantic coasts; mountainous in the central and southern areas

Falkland Islands (Islas Malvinas)

rocky, hilly, mountainous with some boggy, undulating plains

Faroe Islands

rugged, rocky, some low peaks; cliffs along most of coast


mostly mountains of volcanic origin


mostly low, flat to rolling plains interspersed with lakes and low hills


metropolitan France: mostly flat plains or gently rolling hills in north and west; remainder is mountainous, especially Pyrenees in south, Alps in east;

French Guiana: low-lying coastal plains rising to hills and small mountains;

Guadeloupe: Basse-Terre is volcanic in origin with interior mountains; Grande-Terre is low limestone formation; most of the seven other islands are volcanic in origin;

Martinique: mountainous with indented coastline; dormant volcano;

Mayotte: generally undulating, with deep ravines and ancient volcanic peaks;

Reunion: mostly rugged and mountainous; fertile lowlands along coast

French Polynesia

mixture of rugged high islands and low islands with reefs

French Southern and Antarctic Lands

Ile Amsterdam (Ile Amsterdam et Ile Saint-Paul): a volcanic island with steep coastal cliffs; the center floor of the volcano is a large plateau;

Ile Saint-Paul (Ile Amsterdam et Ile Saint-Paul): triangular in shape, the island is the top of a volcano, rocky with steep cliffs on the eastern side; has active thermal springs;

Iles Crozet: a large archipelago formed from the Crozet Plateau is divided into two groups of islands;

Iles Kerguelen: the interior of the large island of Ile Kerguelen is composed of high mountains, hills, valleys, and plains with peninsulas stretching off its coasts;

Bassas da India (Iles Eparses): atoll, awash at high tide; shallow (15 m) lagoon;

Europa Island, Glorioso Islands, Juan de Nova Island: low, flat, and sandy;

Tromelin Island (Iles Eparses): low, flat, sandy; likely volcanic seamount


narrow coastal plain; hilly interior; savanna in east and south

Gambia, The

flood plain of the Gambia River flanked by some low hills

Gaza Strip

flat to rolling, sand- and dune-covered coastal plain


largely mountainous with Great Caucasus Mountains in the north and Lesser Caucasus Mountains in the south; Kolkhet'is Dablobi (Kolkhida Lowland) opens to the Black Sea in the west; Mtkvari River Basin in the east; fertile soils in river valley flood plains and foothills of Kolkhida Lowland


lowlands in north, uplands in center, Bavarian Alps in south


mostly low plains with dissected plateau in south-central area


a narrow coastal lowland borders the Rock of Gibraltar


mountainous with ranges extending into the sea as peninsulas or chains of islands


flat to gradually sloping icecap covers all but a narrow, mountainous, barren, rocky coast


volcanic in origin with central mountains


volcanic origin, surrounded by coral reefs; relatively flat coralline limestone plateau (source of most fresh water), with steep coastal cliffs and narrow coastal plains in north, low hills in center, mountains in south


two east-west trending mountain chains divide the country into three regions: the mountainous highlands, the Pacific coast south of mountains, and the vast northern Peten lowlands


mostly flat with low hills in southwest


generally flat coastal plain, hilly to mountainous interior


mostly low-lying coastal plain with a deeply indented estuarine coastline rising to savanna in east; numerous off-shore islands including the Arquipelago Dos Bijagos consisting of 18 main islands and many small islets


mostly rolling highlands; low coastal plain; savanna in south


mostly rough and mountainous

Heard Island and McDonald Islands

Heard Island - 80% ice-covered, bleak and mountainous, dominated by a large massif (Big Ben) and an active volcano (Mawson Peak); McDonald Islands - small and rocky


mostly mountains in interior, narrow coastal plains

Hong Kong

hilly to mountainous with steep slopes; lowlands in north


mostly flat to rolling plains; hills and low mountains on the Slovakian border


mostly plateau interspersed with mountain peaks, icefields; coast deeply indented by bays and fiords


upland plain (Deccan Plateau) in south, flat to rolling plain along the Ganges, deserts in west, Himalayas in north


mostly coastal lowlands; larger islands have interior mountains


rugged, mountainous rim; high, central basin with deserts, mountains; small, discontinuous plains along both coasts


mostly broad plains; reedy marshes along Iranian border in south with large flooded areas; mountains along borders with Iran and Turkey


mostly flat to rolling interior plain surrounded by rugged hills and low mountains; sea cliffs on west coast

Isle of Man

hills in north and south bisected by central valley


Negev desert in the south; low coastal plain; central mountains; Jordan Rift Valley


mostly rugged and mountainous; some plains, coastal lowlands


mostly mountains, with narrow, discontinuous coastal plain

Jan Mayen

volcanic island, partly covered by glaciers


mostly rugged and mountainous


gently rolling plain with low, rugged hills along north coast


mostly arid desert plateau; a great north-south geological rift along the west of the country is the dominant topographical feature and includes the Jordan River Valley, the Dead Sea, and the Jordanian Highlands


vast flat steppe extending from the Volga in the west to the Altai Mountains in the east and from the plains of western Siberia in the north to oases and deserts of Central Asia in the south


low plains rise to central highlands bisected by Great Rift Valley; fertile plateau in west


mostly low-lying coral atolls surrounded by extensive reefs

Korea, North

mostly hills and mountains separated by deep, narrow valleys; wide coastal plains in west, discontinuous in east

Korea, South

mostly hills and mountains; wide coastal plains in west and south


flat fluvial basin at an elevation of 400-700 m above sea level surrounded by several high mountain ranges with elevations of 2,000 to 2,500 m


flat to slightly undulating desert plain


peaks of the Tien Shan mountain range and associated valleys and basins encompass the entire country


mostly rugged mountains; some plains and plateaus


low plain


narrow coastal plain; El Beqaa (Bekaa Valley) separates Lebanon and Anti-Lebanon Mountains


mostly highland with plateaus, hills, and mountains


mostly flat to rolling coastal plains rising to rolling plateau and low mountains in northeast


mostly barren, flat to undulating plains, plateaus, depressions


mostly mountainous (Alps) with Rhine Valley in western third


lowland, many scattered small lakes, fertile soil


mostly gently rolling uplands with broad, shallow valleys; uplands to slightly mountainous in the north; steep slope down to Moselle flood plain in the southeast


generally flat


narrow coastal plain, high plateau and mountains in center


narrow elongated plateau with rolling plains, rounded hills, some mountains


coastal plains rising to hills and mountains


flat coral atolls, with white sandy beaches; sits atop the submarine volcanic Chagos-Laccadive Ridge


mostly flat to rolling northern plains covered by sand; savanna in south, rugged hills in northeast


mostly low, rocky, flat to dissected plains; many coastal cliffs

Marshall Islands

low coral limestone and sand islands


mostly barren, flat plains of the Sahara; some central hills


small coastal plain rising to discontinuous mountains encircling central plateau


high, rugged mountains; low coastal plains; high plateaus; desert

Micronesia, Federated States of

islands vary geologically from high mountainous islands to low, coral atolls; volcanic outcroppings on Pohnpei, Kosrae, and Chuuk


rolling steppe, gradual slope south to Black Sea


hilly, rugged, rocky


vast semidesert and desert plains, grassy steppe, mountains in west and southwest; Gobi Desert in south-central


highly indented coastline with narrow coastal plain backed by rugged high limestone mountains and plateaus


volcanic island, mostly mountainous, with small coastal lowland


mountainous northern coast (Rif Mountains) and interior (Atlas Mountains) bordered by large plateaus with intermontane valleys, and fertile coastal plains; the south is mostly low, flat desert with large areas of rocky or sandy surfaces 


mostly coastal lowlands, uplands in center, high plateaus in northwest, mountains in west


mostly high plateau; Namib Desert along coast; Kalahari Desert in east


sandy beach rises to fertile ring around raised coral reefs with phosphate plateau in center

Navassa Island

raised flat to undulating coral and limestone plateau; ringed by vertical white cliffs (9 to 15 m high)


Tarai or flat river plain of the Ganges in south; central hill region with rugged Himalayas in north


mostly coastal lowland and reclaimed land (polders); some hills in southeast

New Caledonia

coastal plains with interior mountains

New Zealand

predominately mountainous with large coastal plains


extensive Atlantic coastal plains rising to central interior mountains; narrow Pacific coastal plain interrupted by volcanoes


predominately desert plains and sand dunes; flat to rolling plains in south; hills in north


southern lowlands merge into central hills and plateaus; mountains in southeast, plains in north


steep limestone cliffs along coast, central plateau

Norfolk Island

volcanic island with mostly rolling plains

North Macedonia

mountainous with deep basins and valleys; three large lakes, each divided by a frontier line; country bisected by the Vardar River

Northern Mariana Islands

the southern islands in this north-south trending archipelago are limestone, with fringing coral reefs; the northern islands are volcanic, with active volcanoes on several islands


glaciated; mostly high plateaus and rugged mountains broken by fertile valleys; small, scattered plains; coastline deeply indented by fjords; arctic tundra in north


central desert plain, rugged mountains in north and south


divided into three major geographic areas: the northern highlands, the Indus River plain in the center and east, and the Balochistan Plateau in the south and west


varying topography from the high, mountainous main island of Babelthuap to low, coral islands usually fringed by large barrier reefs


interior mostly steep, rugged mountains with dissected, upland plains; coastal plains with rolling hills

Papua New Guinea

mostly mountains with coastal lowlands and rolling foothills

Paracel Islands

mostly low and flat


grassy plains and wooded hills east of Rio Paraguay; Gran Chaco region west of Rio Paraguay mostly low, marshy plain near the river, and dry forest and thorny scrub elsewhere


western coastal plain (costa), high and rugged Andes in center (sierra), eastern lowland jungle of Amazon Basin (selva)


mostly mountains with narrow to extensive coastal lowlands

Pitcairn Islands

rugged volcanic formation; rocky coastline with cliffs


mostly flat plain; mountains along southern border


the west-flowing Tagus River divides the country: the north is mountainous toward the interior, while the south is characterized by rolling plains

Puerto Rico

mostly mountains with coastal plain in north; precipitous mountains to the sea on west coast; sandy beaches along most coastal areas


mostly flat and barren desert


central Transylvanian Basin is separated from the Moldavian Plateau on the east by the Eastern Carpathian Mountains and separated from the Walachian Plain on the south by the Transylvanian Alps


broad plain with low hills west of Urals; vast coniferous forest and tundra in Siberia; uplands and mountains along southern border regions


mostly grassy uplands and hills; relief is mountainous with altitude declining from west to east

Saint Barthelemy

hilly, almost completely surrounded by shallow-water reefs, with plentiful beaches

Saint Helena, Ascension, and Tristan da Cunha

the islands of this group are of volcanic origin associated with the Atlantic Mid-Ocean Ridge

Saint Helena: rugged, volcanic; small scattered plateaus and plains;

Ascension: surface covered by lava flows and cinder cones of 44 dormant volcanoes; terrain rises to the east;

Tristan da Cunha: sheer cliffs line the coastline of the nearly circular island; the flanks of the central volcanic peak are deeply dissected; narrow coastal plain lies between The Peak and the coastal cliffs

Saint Kitts and Nevis

volcanic with mountainous interiors

Saint Lucia

volcanic and mountainous with broad, fertile valleys

Saint Pierre and Miquelon

mostly barren rock


two main islands (Savaii, Upolu) and several smaller islands and uninhabited islets; narrow coastal plain with volcanic, rugged mountains in interior

San Marino

rugged mountains

Sao Tome and Principe

volcanic, mountainous

Saudi Arabia

mostly sandy desert


generally low, rolling, plains rising to foothills in southeast


extremely varied; to the north, rich fertile plains; to the east, limestone ranges and basins; to the southeast, ancient mountains and hills


Mahe Group is volcanic with a narrow coastal strip and rocky, hilly interior; others are relatively flat coral atolls, or elevated reefs; sits atop the submarine Mascarene Plateau

Sierra Leone

coastal belt of mangrove swamps, wooded hill country, upland plateau, mountains in east


lowlying, gently undulating central plateau

Sint Maarten

low, hilly terrain, volcanic origin


rugged mountains in the central and northern part and lowlands in the south


a short southwestern coastal strip of Karst topography on the Adriatic; an alpine mountain region lies adjacent to Italy and Austria in the north; mixed mountains and valleys with numerous rivers to the east

Solomon Islands

mostly rugged mountains with some low coral atolls


mostly flat to undulating plateau rising to hills in north

South Africa

vast interior plateau rimmed by rugged hills and narrow coastal plain

South Georgia and South Sandwich Islands

most of the islands are rugged and mountainous rising steeply from the sea; South Georgia is largely barren with steep, glacier-covered mountains; the South Sandwich Islands are of volcanic origin with some active volcanoes

South Sudan

plains in the north and center rise to southern highlands along the border with Uganda and Kenya; the White Nile, flowing north out of the uplands of Central Africa, is the major geographic feature of the country; The Sudd (a name derived from floating vegetation that hinders navigation) is a large swampy area of more than 100,000 sq km fed by the waters of the White Nile that dominates the center of the country


large, flat to dissected plateau surrounded by rugged hills; Pyrenees Mountains in north

Spratly Islands

small, flat islands, islets, cays, and reefs

Sri Lanka

mostly low, flat to rolling plain; mountains in south-central interior


generally flat, featureless plain; desert dominates the north


mostly rolling hills; narrow coastal plain with swamps


rugged mountains; much of the upland areas are ice covered; west coast clear of ice about half the year; fjords along west and north coasts


mostly flat or gently rolling lowlands; mountains in west


mostly mountains (Alps in south, Jura in northwest) with a central plateau of rolling hills, plains, and large lakes


primarily semiarid and desert plateau; narrow coastal plain; mountains in west


eastern two-thirds mostly rugged mountains; flat to gently rolling plains in west


mountainous region dominated by the Alay Mountains in the north and the Pamirs in the southeast; western Fergana Valley in north, Kofirnihon and Vakhsh Valleys in southwest


plains along coast; central plateau; highlands in north, south


central plain; Khorat Plateau in the east; mountains elsewhere




gently rolling savanna in north; central hills; southern plateau; low coastal plain with extensive lagoons and marshes


low-lying coral atolls enclosing large lagoons


mostly flat islands with limestone bedrock formed from uplifted coral formation; others have limestone overlying volcanic rock

Trinidad and Tobago

mostly plains with some hills and low mountains


mountains in north; hot, dry central plain; semiarid south merges into the Sahara

Turkey (Turkiye)

high central plateau (Anatolia); narrow coastal plain; several mountain ranges


flat-to-rolling sandy desert with dunes rising to mountains in the south; low mountains along border with Iran; borders Caspian Sea in west

Turks and Caicos Islands

low, flat limestone; extensive marshes and mangrove swamps


low-lying and narrow coral atolls


mostly plateau with rim of mountains


mostly fertile plains (steppes) and plateaus, with mountains found only in the west (the Carpathians) or in the extreme south of the Crimean Peninsula

United Arab Emirates

flat, barren coastal plain merging into rolling sand dunes of vast desert; mountains in east

United Kingdom

mostly rugged hills and low mountains; level to rolling plains in east and southeast

United States

vast central plain, mountains in west, hills and low mountains in east; rugged mountains and broad river valleys in Alaska; rugged, volcanic topography in Hawaii

United States Pacific Island Wildlife Refuges

low and nearly flat sandy coral islands with narrow fringing reefs that have developed at the top of submerged volcanic mountains, which in most cases rise steeply from the ocean floor


mostly rolling plains and low hills; fertile coastal lowland


mostly flat-to-rolling sandy desert with dunes; broad, flat intensely irrigated river valleys along course of Amu Darya, Syr Darya (Sirdaryo), and Zaravshan; Fergana Valley in east surrounded by mountainous Tajikistan and Kyrgyzstan; shrinking Aral Sea in west


mostly mountainous islands of volcanic origin; narrow coastal plains


Andes Mountains and Maracaibo Lowlands in northwest; central plains (llanos); Guiana Highlands in southeast


low, flat delta in south and north; central highlands; hilly, mountainous in far north and northwest

Virgin Islands

mostly hilly to rugged and mountainous with little flat land

Wake Island

atoll of three low coral islands, Peale, Wake, and Wilkes, built up on an underwater volcano; central lagoon is former crater, islands are part of the rim

Wallis and Futuna

volcanic origin; low hills

West Bank

mostly rugged, dissected upland in west, flat plains descending to Jordan River Valley to the east


tremendous variation of terrain may be found on each of the continents; check the World "Elevation" entry for a compilation of terrain extremes; the world's ocean floors also display extraordinary variation while the ocean surfaces form a dynamic, continuously changing environment; check the "Bathymetry" and "Major surface currents" entries under each of the five ocean entries (Arctic, Atlantic, Indian, Pacific, and Southern) for further information on oceanic environs

Ten Cave Superlatives: compiled from "Geography - note(s)" under various country entries where more details may be found

largest cave: Son Doong in Phong Nha-Ke Bang National Park, Vietnam is the World's largest cave (greatest cross sectional area) and is the largest known cave passage in the world by volume; it currently measures a total of 38.5 million cu m (about 1.35 billion cu ft); it connects to Thung cave (but not yet officially); when recognized, it will add an additional 1.6 million cu m in volume

largest ice cave:
the Eisriesenwelt (Ice Giants World) inside the Hochkogel mountain near Werfen, Austria is the World's largest and longest ice cave system at 42 km (26 mi)

longest cave:
Mammoth Cave, in west-central Kentucky, is the World's longest known cave system with more than 650 km (405 mi) of surveyed passageways

longest salt cave: the Malham Cave in Mount Sodom in Israel is the World's longest salt cave at 10 km (6 mi); its survey is not complete and its length will undoubtedly increase

longest underwater cave: the Sac Actun cave system in Mexico at 348 km (216 mi) is the longest underwater cave in the World and the second longest cave worldwide

longest lava tube cave: Kazumura Cave on the island of Hawaii is the World's longest and deepest lava tube cave; it has been surveyed at 66 km (41 mi) long and 1,102 m (3,614 ft) deep

deepest cave: Veryovkina Cave in the Caucasus country of Georgia is the World's deepest cave, plunging down 2,212 m (7,257 ft)

deepest underwater cave: the Hranice Abyss in Czechia is the World's deepest surveyed underwater cave at 404 m (1,325 ft); its survey is not complete and it could end up being some 800-1,200 m deep

largest cave chamber: the Miao Room in the Gebihe cave system at China's Ziyun Getu He Chuandong National Park encloses some 10.78 million cu m (380.7 million cu ft) of volume

largest bat cave: Bracken Cave outside of San Antonio, Texas is the World's largest bat cave; it is the summer home to the largest colony of bats in the World; an estimated 20 million Mexican free-tailed bats roost in the cave from March to October making it the World's largest known concentration of mammals

bonus "cave" - the world's largest sinkhole: the Xiaoxhai Tiankeng sinkhole in Chongqing Municipality, China is 660 m deep, with a volume of 130 million cu m


narrow coastal plain backed by flat-topped hills and rugged mountains; dissected upland desert plains in center slope into the desert interior of the Arabian Peninsula


mostly high plateau with some hills and mountains


mostly high plateau with higher central plateau (high veld); mountains in east