Mountains Information And Facts | National Geographic

1 of 8Mount Kinabalu, MalaysiaFog obscures the summit of Malaysia's Mount Kinabalu, a 13,455-foot (4,101-meter) peak in northwestern East Malaysia. Formerly known as St. Peter's Mount, Kinabalu is the highest mountain in the Malay Archipelago.Photograph by Jose Azel

• SCIENCE
• REFERENCE

Mountains

They define landscapes, people risk their lives to climb them, and they can even make their own weather.

3 min read

The mighty chunks rise all over the world, including the oceans. They usually have steep, sloping sides and sharp or rounded ridges, and a high point, called a peak or summit. Most geologists classify a mountain as a landform that rises at least 1,000 feet (300 meters) or more above its surrounding area. A mountain range is a series or chain of mountains that are close together.

How Are Mountains Formed?

The world's tallest mountain ranges form when pieces of Earth's crust—called plates—smash against each other in a process called plate tectonics, and buckle up like the hood of a car in a head-on collision. The Himalaya in Asia formed from one such massive wreck that started about 55 million years ago. Thirty of the world’s highest mountains are in the Himalaya. The summit of Mount Everest, at 29,035 feet (8,850 meters), is the highest point on Earth.

The tallest mountain measured from top to bottom is Mauna Kea, an inactive volcano on the island of Hawaii in the Pacific Ocean. Measured from the base, Mauna Kea stands 33,474 feet (10,203 meters) tall, though it only rises 13,796 feet (4,205 meters) above the sea.

Volcanic mountains form when molten rock from deep inside the Earth erupts through the crust and piles up on itself. The islands of Hawaii were formed by undersea volcanoes, and the islands seen above water today are the remaining volcano tops. Well-known volcanoes on land include Mount St. Helens in Washington State and Mount Fuji in Japan. Sometimes volcanic eruptions break down mountains instead of building them up, like the 1980 eruption that blew the top off Mount St. Helens.

When magma pushes the crust up but hardens before erupting onto the surface, it forms so-called dome mountains. Wind and rain pummel the domes, sculpting peaks and valleys. Examples include the Black Hills of South Dakota and the Adirondack Mountains of New York. Plateau mountains are similar to dome mountains, but form as colliding tectonic plates push up the land without folding or faulting. They are then shaped by weathering and erosion.

Other types of mountains form when stresses within and between the tectonic plates lead to cracking and faulting of the Earth's surface, which forces blocks of rock up and down. Examples of fault-block mountains include the Sierra Nevada in California and Nevada, the Tetons in Wyoming, and the Harz Mountains in Germany.

Impact of Mountains on Habitats and Geopolitics

Mountains often serve as geographic features that define natural borders of countries. Their height can influence weather patterns, stalling storms that roll off the oceans and squeezing water from the clouds. The other side is often much drier. The rugged landscapes even provide refuge—and protection—for fleeing and invading armies.

Related Topics

• MOUNTAINS
• EARTH SCIENCES
• VOLCANOES
• PLATE TECTONICS

You May Also Like

SCIENCE

Santorini’s volcano is hiding an explosive secret

SCIENCE

There's a frozen labyrinth atop Mount Rainier. What secrets does it hold?

SCIENCE

Why Iceland's latest eruption may be the most dangerous in recent history

Volcanoes—everything to know about nature’s geologic architects

SCIENCE

What causes earthquakes?

Legal

• Terms of Use
• Privacy Policy
• Your US State Privacy Rights
• Children's Online Privacy Policy
• Interest-Based Ads
• About Nielsen Measurement
• Do Not Sell or Share My Personal Information

Our Sites

• Nat Geo Home
• Attend a Live Event
• Book a Trip
• Buy Maps
• Inspire Your Kids
• Shop Nat Geo
• Visit the D.C. Museum
• Watch TV
• Learn About Our Impact
• Support Our Mission
• Masthead
• Press Room
• Advertise With Us

Join Us

• Subscribe
• Customer Service
• Renew Subscription
• Manage Your Subscription
• Work at Nat Geo
• Sign Up for Our Newsletters
• Contribute to Protect the Planet

Follow usNational Geographic InstagramNational Geographic FacebookNational Geographic TwitterNational Geographic YoutubeNational Geographic LinkedinNational Geographic TiktokNational Geographic RedditUnited States (Change)

Copyright © 1996-2015 National Geographic SocietyCopyright © 2015-2026 National Geographic Partners, LLC. All rights reserved