Natural wonder North America
Adirondack Mountains
The Adirondack Mountains are in New York, in the United States. They have forests, lakes and rocky peaks.
The Adirondack Mountains in New York State form a round cluster of peaks, not a long chain. NASA says they are made of rock more than a billion years old that began rising as a dome about five million years ago, and they are still rising.
The Adirondacks are a dome of rock more than a billion years old, uplifted from about five million years ago and still rising two to three millimeters a year (NASA). The Adirondack Park, created by New York State in 1892, covers about 6 million acres with over 3,000 lakes.
Photo: Jessica Dubé, CC BY-SA 3.0, via Wikimedia Commons
Discover the Adirondack Mountains
The Adirondack Mountains are in New York State. Forests cover them, and there are thousands of lakes.
In this photo, green mountains rise under white clouds, behind bare rock.
The Adirondacks are clustered together in a circle rather than a long chain, NASA explains. The mountains lie in the Adirondack Park, which New York State created in 1892. It covers about 6 million acres and has over 3,000 lakes.
This photo by Jessica Dubé, taken in May 2008, shows the Adirondacks in spring: forested ridges and peaks under clouds, with bare rock in front.
NASA's Earth Observatory describes the Adirondacks as a circle rather than a chain. The Adirondack Park Agency calls the park the largest publicly protected area in the contiguous United States: about 6 million acres, nearly half of it state Forest Preserve kept 'forever wild' and the rest private land with towns, farms, timber lands and homes.
The hero photo (Jessica Dubé, GFDL and CC BY-SA 3.0) shows the Adirondacks in spring, 24 May 2008: forested ridges, a valley and peaks under clouds, seen from a rock slab.
- Shape
- a dome: a circle of mountains, not a chain
- Adirondack Park
- about 6 million acres
- Lakes in the park
- over 3,000
Ancient rock in a young dome
The rock in these mountains is very, very old.
But the mountains are still slowly rising!
NASA says the rock of the Adirondacks is more than a billion years old, but it was pushed up into a dome only about five million years ago. The mountains are still rising, two to three millimeters a year.
Straight valleys cross the dome from northeast to southwest. They look like scratches left by glaciers, but NASA says they formed along faults.
The mountains are made of rock more than a billion years old, uplifted in a dome starting about five million years ago and still rising two to three millimeters per year (NASA). Straight valleys, many holding rivers or lakes, cross the dome northeast to southwest; they formed along faults.
Why the dome rose was long a mystery. In 2018, UMass Amherst seismologists mapped low-density material, in which seismic waves travel slowly, 50-85 km beneath the mountains and suggested that rising asthenosphere, perhaps with thermal expansion, may have pushed the dome up.
Forests, lakes and loons
Forests and lakes cover the Adirondacks.
Loons, birds with a yodel-like call, nest on the lakes.
The Adirondack Park Agency counts over 3,000 lakes and 30,000 miles of rivers and streams in the park, with globally unique wetlands and old-growth forests. In late fall, a NASA satellite image showed green veins of evergreen forest after the leaves of the deciduous trees had fallen.
In New York, common loons breed on the lakes of the Adirondack Mountains. Their call is an eerie, yodel-like sound.
The park has over 3,000 lakes, 30,000 miles of rivers and streams and a wide variety of habitats, including globally unique wetland types and old-growth forests (APA). A November 2009 satellite image showed veins of evergreen forest across the mountains once the deciduous trees had dropped their leaves (NASA).
The New York State Department of Environmental Conservation (DEC) lists the common loon (Gavia immer) as a species of special concern; in New York it breeds on Adirondack lakes and the St. Lawrence River region, eats almost only fish and prefers lakes of 25 acres or more. DEC notes lake acidification and mercury as problems for Adirondack loons.
Hiking safely
Wear sturdy boots and layers, and carry water and food.
Check the weather, and be back before dark.
The DEC's Hike Smart NY advice says to wear sturdy boots and layered clothing that keeps skin dry, and to avoid cotton. Carry a map, a waterproof jacket, a hat and gloves, food, at least 2 liters of water per person, and sun and insect protection.
Check the weather for the day and night of your trip, know when the sun sets, and plan to be back before dark.
Hike Smart NY lists 10 essentials for every hike: navigation, insulation and rain gear, light, first aid, an emergency kit, fire, extra food, water (at least 2 liters per person), sun and insect protection, and emergency shelter. It recommends moisture-wicking synthetic layers, not cotton, even in summer, and light colors that make ticks easier to see.
Plan where you are going and when you will return, check trail conditions, choose trails within your group's ability, check the forecast for the day and the following night, and plan to return before dark.
Amazing facts
-
These mountains are still growing a tiny bit every year!
NASA says the Adirondacks are still rising, two to three millimeters a year.
NASA: the Adirondack dome, uplifted from about five million years ago, continues to rise two to three millimeters per year.
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The Adirondack Park is bigger than four famous national parks put together.
The Adirondack Park is bigger than Yellowstone, Everglades, Glacier and Grand Canyon national parks combined.
The Adirondack Park Agency says the park is greater in size than Yellowstone, Everglades, Glacier and Grand Canyon national parks combined.
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Loons on Adirondack lakes have a call that sounds like yodeling.
The common loon has an eerie, yodel-like call, heard on the northern lakes where it nests.
DEC: the loon's eerie, yodel-like call can be heard on northern lakes where it nests; pairs are believed to mate for life.
Words to know
- dome
- a round area of land pushed up in the middle, like an upside-down bowl
- uplift
- the slow raising of land to a higher level
- fault
- a crack in Earth's crust where rocks have moved
- deciduous
- describes trees that drop their leaves each year
- asthenosphere
- a weak, slowly flowing layer of Earth beneath the rigid outer shell
Discovery challenge
-
What shape do the Adirondack Mountains make?
What shape does NASA say the Adirondack Mountains make?
How does NASA describe the arrangement of the Adirondack Mountains?
- A circle, like a dome
- A long straight line
- A triangle
Show the answer
A circle, like a dome
A circle, like a dome.
A circle rather than a chain: a dome.
Clustered together in a circle rather than a chain, uplifted as a dome.
-
Are the Adirondacks still rising?
How fast does NASA say the Adirondacks are rising?
What present-day uplift rate does NASA give for the Adirondacks?
- Yes, 2 to 3 millimeters a year
- No, they are sinking fast
- Yes, 2 to 3 meters a year
Show the answer
Yes, 2 to 3 millimeters a year
Yes, a tiny bit every year: 2 to 3 millimeters.
Two to three millimeters a year.
Two to three millimeters per year.
-
How old is the rock in the Adirondacks?
How old is the rock of the Adirondack Mountains?
What age does NASA give for the Adirondacks' rock?
- More than a billion years old
- About 100 years old
- About 1,000 years old
Show the answer
More than a billion years old
More than a billion years old!
More than a billion years old, though the dome rose much later.
More than a billion years old; the dome uplift began about five million years ago.
-
Which bird with a yodel-like call nests on Adirondack lakes?
Which bird breeds on the lakes of the Adirondack Mountains?
Which species of special concern does DEC say breeds on Adirondack lakes?
- The common loon
- The flamingo
- The ostrich
Show the answer
The common loon
The common loon.
The common loon, with its yodel-like call.
The common loon (Gavia immer).
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What should you wear on a hike instead of cotton?
What does Hike Smart NY say to wear instead of cotton?
What clothing does Hike Smart NY recommend, and why avoid cotton?
- Layers that keep your skin dry
- A wet T-shirt
- Nothing warm at all
Show the answer
Layers that keep your skin dry
Layers that keep you dry.
Layered, moisture-wicking clothing; cotton holds moisture.
Moisture-wicking synthetic layers, even in summer, because cotton holds moisture.
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For parents & teachers
What children will learn
- Locate the Adirondack Mountains in New York State.
- Explain how old rock can form young mountains in a dome.
- Describe the Adirondack Park's lakes, forests and loons.
- Know the essentials for a safe hike.
Recommended ages: 3 to 17 · About 15 minutes
Talk about it
- How can mountains made of very old rock be young mountains?
- Why might a round dome of mountains look different from a long mountain chain?
- Why do hikers carry more water and warm clothes than they think they will need?
Try at home or in class
- Put a balloon under a towel and slowly blow it up to see how land can bulge into a dome.
- Make your own list of the 10 hiking essentials and pack a practice day bag with a grown-up.
Key vocabulary: dome, uplift, fault, deciduous, asthenosphere
Where these facts come from
- Wikidata , Wikimedia Foundation (CC0 1.0)
- Late Fall in the Adirondack Mountains , NASA Earth Observatory
- About the Adirondack Park , Adirondack Park Agency (New York State)
- UMass Amherst Geoscientists Offer New Evidence for How the Adirondack Mountains Formed , University of Massachusetts Amherst
- Common Loon , New York State Department of Environmental Conservation
- Hike Smart NY , New York State Department of Environmental Conservation
- File:Adirondacks printemps 2008.JPG , Wikimedia Commons
- Natural Earth vector data , Natural Earth (NACIS) (Public domain)
- Wikimedia Commons , Wikimedia Foundation (Per file (public domain, CC0, CC BY or CC BY-SA); see each media record)
Checked, not yet human-reviewed. Last updated November 1, 2026. Spotted a mistake? Tell us.