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Geography Types of volcanoes Volcanoes come in different shapes. Runny lava builds wide, gentle shield volcanoes like Mauna Loa. Sticky lava and ash build tall, steep stratovolcanoes like Mount Fuji. Small cinder cones grow from bits of lava thrown into the air. Whether lava is runny or sticky, and how much gas it holds, decides the shape and how explosive the eruptions are.
Natural wonder Andes The Andes run down the whole western side of South America, from the Caribbean coast to the continent's southern tip, through seven countries. Britannica measures them at about 8,900 kilometers, and their highest peak, Aconcagua, rises to 6,959 meters. They are still growing as one plate of Earth's crust slides under another, which is why the Andes have so many volcanoes and earthquakes.
Country Chile Chile stretches about 4,300 kilometers along the west coast of South America, between the Andes and the Pacific Ocean, but it averages only about 180 kilometers wide. Its north holds one of the driest deserts on Earth, and its south is cold, wet and full of fjords and ice.
Country Italy Italy is a country in southern Europe on a long peninsula that reaches into the Mediterranean Sea, often described as shaped like a boot. The Alps rise in the north, the Apennine mountains run down its length, and about 58.9 million people (2026) live there. Its capital is Rome.
Country Japan Japan is an island country in East Asia. Most of its land is steep mountains and forest, Mount Fuji is its tallest peak, and about 124 million people live there, many of them in big cities such as Tokyo.
Country Mexico Mexico is a large country in southern North America, between the Pacific Ocean and the Gulf of Mexico. It has smoking volcanoes, ancient cities built by the Maya and other peoples, and about 132 million people, many of them in and around Mexico City.
Country Rwanda Rwanda is a small, landlocked country in east-central Africa, just south of the equator. It is often called the land of a thousand hills. Mountain gorillas live among its volcanoes in the northwest, Lake Kivu lies on its western edge, and about 14.6 million people lived there in 2025.
Country Armenia Armenia is a small, landlocked country just south of the Caucasus mountains. Most of it is high mountains and plateaus, its tallest peak is Mount Aragats, and about 3.1 million people lived there in 2025.
Country Ecuador Ecuador is a country in northwestern South America, named after the equator, which crosses it. In a small space it holds Pacific beaches, high snowy volcanoes of the Andes, part of the Amazon rainforest and the Galápagos Islands, whose wildlife helped Charles Darwin develop his ideas.
Country Iceland Iceland is an island country in the North Atlantic, close to the Arctic Circle. It sits on the border between two giant plates of Earth's crust and has about 200 volcanoes, many hot springs and huge glaciers, and about 396,500 people lived there in mid-2026.
Country Cameroon Cameroon sits where western and central Africa meet. In the south are thick rainforests full of monkeys and apes, by the coast rises Mount Cameroon, an active volcano, and in the north are dry savanna plains. About 29.9 million people lived there in 2025, and French and English are both official languages.
Country Djibouti Djibouti is a small country in the Horn of Africa, where the Red Sea meets the Gulf of Aden. It is hot and dry, with volcanic rock everywhere, and Lake Assal, 155 meters below sea level, is the lowest point in Africa. About 1.2 million people lived there in 2025, most of them in the capital, also called Djibouti.
Country Indonesia Indonesia is a country of about 17,500 islands in Southeast Asia, spread across the Equator between the Indian and Pacific oceans. It has more than 100 active volcanoes, rainforests full of wildlife, and about 286 million people (2025).
Country Cabo Verde Cabo Verde is a country made of ten islands in the Atlantic Ocean, about 620 kilometers off the coast of West Africa. Some islands are flat and sandy, others are steep and volcanic, and rain is rare. Its people are famous for their music, and the 2021 census counted about 491,000 people living there.
Country Costa Rica Costa Rica is a small country in Central America between the Caribbean Sea and the Pacific Ocean. Volcanoes and mountains run down its middle, its forests are full of wildlife, and many national parks protect them. Since 1949 it has had no army. About 5.2 million people lived there in 2025.
Natural wonder Mount Etna Mount Etna is a huge, active volcano on the east coast of Sicily, in Italy. UNESCO calls it the most active stratovolcano in the world, and people have written about its eruptions for at least 2,700 years. Its height changes as eruptions build it up and crater rims collapse. Vineyards and orchards grow on its rich lower slopes, and scientists watch it every day.
Natural wonder Mount Fuji Mount Fuji, 3,776 meters high, is the highest mountain in Japan and an active volcano that last erupted in 1707. Its almost perfect cone was built by three volcanoes, one on top of another, and it has inspired artists for hundreds of years.
Natural wonder Mount Kenya Mount Kenya is the second highest mountain in Africa, 5,199 meters tall, standing just south of the Equator in central Kenya. It is an old volcano that stopped erupting millions of years ago and has been carved by glaciers into sharp rocky peaks. Its slopes climb through farms, forests, bamboo and strange giant plants up to small, shrinking glaciers.
Country New Zealand New Zealand, also called Aotearoa, is an island country in the South Pacific. Its two main islands have snowy mountains, glaciers, volcanoes and deep fiords, and about 5.36 million people lived there in 2026.
Country Philippines The Philippines is an island country in Southeast Asia, in the western Pacific Ocean. It has more than 7,000 islands, about 50 volcanoes and rich coral reefs, and about 112.7 million people were counted there in 2024.
Natural wonder Vatnajökull Vatnajökull, in southeastern Iceland, is a huge ice cap covering about 7,500 square kilometers. It is Europe's largest ice cap by volume. Volcanoes lie hidden beneath the ice, and when they erupt, melting ice can burst out in sudden floods. The ice cap sits at the heart of Vatnajökull National Park, a World Heritage Site of "fire and ice".
Natural wonder Mount Ararat Mount Ararat is a huge volcanic mountain in the far east of Türkiye, close to where Türkiye, Iran and Armenia meet. It has two peaks: Great Ararat, about 5,165 meters high and the tallest mountain in Türkiye, and the smaller, cone-shaped Little Ararat. Snow covers the top all year, and a glacier clings to its north side.
Natural wonder Mount Elbrus Mount Elbrus is the highest peak of the Caucasus Mountains, in southwestern Russia. It is an old volcano with two snow-covered tops, the higher one 5,642 meters tall. Twenty-two glaciers cover its slopes and feed rivers below. Whether it counts as Europe's highest mountain depends on where you draw the line between Europe and Asia.
Natural wonder Easter Island Easter Island, called Rapa Nui by its first people, is a small volcanic island in the Pacific Ocean, about 3,540 kilometers west of Chile. Polynesian settlers who arrived long ago carved more than 600 giant stone statues, called moai, from the rock of a volcano and set many of them on stone platforms. Today the island's national park is a World Heritage Site cared for by the Rapa Nui people.
Natural wonder Mount Vesuvius Mount Vesuvius is an active volcano that rises above the Bay of Naples in southern Italy. In AD 79 it erupted and buried the Roman towns of Pompeii and Herculaneum, which people can visit today. Its last eruption was in 1944. Because more than two million people live around it, scientists watch it closely, and Italy has a plan to keep everyone safe.
Natural wonder Eyjafjallajökull Eyjafjallajökull is an ice cap in southern Iceland that covers a volcano. In 2010 the volcano erupted for the first time since 1821. Melting ice and hot lava made very fine ash, and winds carried it over Europe. To keep passengers safe, more than 100,000 flights were canceled in one week of April.
Natural wonder Giant's Causeway The Giant's Causeway, on the north coast of Northern Ireland, is made of some 40,000 columns of dark basalt rock, many of them six-sided, packed together like a honeycomb. They formed about 60 million years ago, when a deep pool of lava cooled slowly, shrank and cracked into columns.
Natural wonder Galápagos Islands The Galápagos Islands are a group of volcanic islands in the Pacific Ocean, about 1,000 kilometers off the coast of Ecuador. Many of their animals live nowhere else on Earth, and they helped inspire Charles Darwin's theory of evolution by natural selection.
Natural wonder Great Rift Valley The Great Rift Valley is a huge valley that runs through East Africa, where the continent is slowly being stretched and pulled apart. Long, steep cliffs line its sides, its floor holds lakes full of flamingos, and giant volcanoes such as Kilimanjaro and Mount Kenya rose beside it. Scientists think a new ocean may one day open here.
Natural wonder Mount Kilimanjaro Mount Kilimanjaro, in northeastern Tanzania, is what UNESCO calls the highest mountain in Africa: its top is 5,895 meters high. It is a huge volcanic mountain standing alone above the plains, and as you climb it you pass through farms, forest, moorland and high alpine desert to its icy top.
Natural wonder Virunga National Park Virunga National Park, in the east of the Democratic Republic of the Congo, was founded in 1925; the park describes itself as Africa's first national park. It stretches from active volcanoes in the south to the snowy Rwenzori Mountains in the north. About one third of the world's mountain gorillas live in its forests, along with elephants, hippos, chimpanzees and hundreds of kinds of birds.
Natural wonder Yellowstone National Park Yellowstone National Park sits on top of a giant volcano in the western United States. Heat from melted rock deep underground powers more than 10,000 hot springs, geysers, mudpots and steam vents, and the park is home to bison, wolves and two kinds of bears.
Geography Why the Ring of Fire exists The Ring of Fire is a horseshoe-shaped path about 40,000 kilometers long around the edges of the Pacific Ocean, with more than 450 volcanoes. It exists because around most of the Pacific, ocean plates are sinking under other plates, which makes magma, deep trenches and earthquakes.
Country Democratic Republic of the Congo The Democratic Republic of the Congo, or DR Congo, is the second-largest country in Africa. The mighty Congo River curves through its rainforests, volcanoes rise in the east, and its capital, Kinshasa, is a center of music, fashion and popular culture.
Landmark Pompeii Pompeii was a Roman town near Naples, in Italy. In 79 CE the volcano Vesuvius erupted and buried it under ash and small stones. Digging began in 1748, and today you can walk its streets, shops, baths and houses. In 2025, 4,000,090 people visited.
Natural wonder Mount Agung Mount Agung is a cone-shaped volcano on the eastern end of Bali, in Indonesia, and the island's highest point at about 3,000 meters. It erupted strongly in 1963 and 1964, and again with explosions, ash clouds and lava in its crater from 2017 to 2019. Scientists watch it all the time and set safety zones around it when it is restless.
Natural wonder Mount Nyiragongo Mount Nyiragongo is a steep volcano in the Virunga Mountains of the Democratic Republic of the Congo, near the border with Rwanda and just north of Lake Kivu. It is 3,470 meters high, and its deep summit crater often holds a lake of bubbling lava. Its lava is very runny, and eruptions in 1977, 2002 and 2021 sent lava flowing down its sides toward the city of Goma.
Geography Islands An island is a piece of land surrounded by water that is smaller than a continent. Islands form in different ways: some broke away from continents, some were built by volcanoes on the sea floor, and some were made by corals or by waves piling up sand. Because they are cut off by water, islands often have unusual plants and animals.
Geography Tectonic plates Earth's hard outer shell is cracked into a dozen or so giant pieces called tectonic plates. They carry the continents and oceans and move a few centimeters a year. Where plates pull apart, push together or slide past each other, we find volcanoes, mountains and earthquakes.
Geography Coasts and beaches Coasts are where land meets the sea, and they are always changing. Waves wear away rocky cliffs into caves, arches and stacks. Rivers and waves carry sand along the shore to build beaches. Beach sand can come from rocks worn down over millions of years, from volcanoes, from tiny shells, and even from fish!
Geography How mountains form Most mountains are built by moving tectonic plates. When continents collide, rock crumples and folds into ranges like the Himalayas. Where the crust stretches and cracks, blocks of rock tilt up along faults. Volcanoes build mountains from lava and ash. Then erosion slowly wears them all down.
Natural wonder Komodo National Park Komodo National Park, in Indonesia, is a group of rugged, dry islands between Sumbawa and Flores. Its three main islands, Komodo, Rinca and Padar, were made by volcanoes. The park contains most of the places where wild Komodo dragons, the largest living lizards, still live, along with rich coral reefs visited by turtles, dolphins and whales.
Natural wonder Aconcagua Aconcagua, in the Andes of Argentina near the border with Chile, is the highest mountain in the Western Hemisphere. Its height has been measured several ways: a 2012 expedition backed by Argentina's National Geographic Institute found 6,960.8 meters. Aconcagua formed from an old volcano, but it is not an active volcano today, and climbers first reached its top in 1897.
Natural wonder Ngorongoro Conservation Area The Ngorongoro Conservation Area in northern Tanzania holds the Ngorongoro Crater, a giant bowl about 16 to 20 kilometers across, left when an ancient volcano collapsed about 2.5 million years ago. Around 25,000 large animals live in and around the crater. The area also protects Olduvai Gorge and Laetoli, where scientists have found important evidence of how humans evolved.