This Alaskan valley exploded with the force of 30 atomic bombs — now it’s a hiker’s paradise

Griggs’ Deadly Trek Through Alaska’s Scalding Ash Valley

In 1912, Alaska’s Novarupta volcano blew its top in the largest eruption of the 20th century. Four years later, botanist Robert Griggs spotted a small puff of steam while hiking Katmai Pass.

What he found next shocked him: tens of thousands of fumaroles hissing from a vast ash valley. Griggs led brave teams back in 1917, walking on ash still hot enough to cook them alive.

They took samples from spots reaching 809 degrees, used steam vents to cook meals, and mapped a place where columns of vapor shot 1,000 feet high.

Their work caught the nation’s eye and soon led President Wilson to create Katmai National Monument in 1918.

The Valley of Ten Thousand Smokes waits for modern explorers at Katmai National Park.

Alaska’s Largest Volcanic Eruption Shook the World in 1912

The Novarupta volcano exploded on June 6, 1912, around 1 PM in remote Alaska. It kept erupting for 60 hours straight, making it the biggest volcanic blast of the 1900s.

Ash shot up over 100,000 feet high, creating a cloud more than 1,000 miles wide. It pumped out 30 times more magma than Mount St.Helens did in 1980.

Within just 4 hours, ash started falling on Kodiak Island. Waves of scorching ash as hot as 2,000 degrees rushed through the Ukak River valley.

Botanist Robert Griggs Led the First Expedition to Study Plant Recovery

Robert Griggs went to Alaska in 1915 leading the first National Geographic Society team to check out what happened after the huge eruption.

He visited Kodiak Island in 1913 and saw a grim sight – mostly empty land with a few tough plants poking through the ash. When he came back in 1915, he got a surprise – the island turned green again.

The ash worked like mulch, helping soil hold moisture. Griggs wanted to get closer to ground zero but his team got stuck in thigh-deep quicksand.

A Tiny Puff of Steam Led to an Amazing Discovery

On July 31, 1916, Griggs spotted something that changed everything. While hiking up Katmai Pass with two friends, he noticed a small wisp of steam in the distance.

What he saw next left him speechless – the whole valley filled with thousands of steam vents pouring from cracks in the ground.

Griggs later wrote that it looked like “another Yellowstone Park” that nobody, not even locals, knew existed until that very moment.

The Team Rushed Back with More Scientists and Equipment

In June 1917, Griggs hurried back to the steaming valley. The 1917 crew included experts in chemistry, zoology, mapping, and botany.

He brought twelve National Geographic Society explorers to the Katmai coast for a proper scientific study.

Griggs worried the steam vents might have stopped, but found the opposite – the valley still pumped out massive amounts of steam, gas, and smoke.

The team took an impressive 4,839 black and white photos between 1913-1919.

Scientists Tiptoed Across Ground Hot Enough to Cook Them Alive

The twelve adventurers spent a month walking through the ash-filled Katmai River valley in both fear and excitement. They carefully picked their steps across the crumbly, dangerous surface.

The volcanic ash piled up to 660 feet thick and once reached temperatures of 1,380 degrees. Even in 1917, holes dug just 3 feet deep reached near-boiling temperatures.

Their bedding got so hot they couldn’t lie on it without constantly turning over, “like being on a rotisserie.

Thousands of Steam Vents Created an Otherworldly Landscape

The team studied the roaring steam vents and checked out the dangerous edges of the volcanic deposits. Griggs counted more than 1,000 fumaroles with steam plumes rising over 500 feet high.

In 1918, researchers found 86 vents hotter than 190°C, with the hottest reaching 432°C. Tests showed the steam was 99.5% water vapor mixed with acidic gases.

The explorers got creative and used a nearby steam vent to cook their food and a glacier as a refrigerator.

The Team Collected Samples While Dodging Danger at Every Step

Through the long Alaska summer days, the scientists grabbed chemical and rock samples, took photos, and drew rough maps.

Griggs noted many different smells in the valley, including sulfur dioxide, hydrochloric acid, and hydrogen sulfide.

Team members counted millions of volcanic vents, finding two main types: round fumaroles and long crack-like fissures.

One team member noticed a bonus to all the steam – they didn’t feel sore from their hard work thanks to the natural outdoor sauna effect.

National Geographic Magazine Turned Griggs Into a Celebrity Explorer

Griggs wrote such vivid stories about Katmai that he sparked interest in the growing conservation movement.

National Geographic published his expedition articles with 47 pictures, including a special fold-out image measuring 8¼ by 25½ inches.

In his report, Griggs wrote that if the same eruption happened on Manhattan Island, people in Chicago would have heard the explosions and Philadelphia would have been buried under a foot of ash.

He called the Valley of Ten Thousand Smokes “a landscape unparalleled anywhere.

Griggs Fought Hard to Protect the Steaming Valley

Griggs and the National Geographic Society pushed non-stop to save the area from development.

National Geographic Society president Gilbert Hovey Grosvenor worked with National Park Service acting director Horace M. Albright on the best approach.

Albright suggested they protect it as a national monument using the Antiquities Act of 1906 since getting a national park through Congress seemed unlikely.

After the 1918 expedition confirmed the Valley of Ten Thousand Smokes wasn’t going away soon, they prepared paperwork to protect 1,080,000 acres.

President Wilson Created the Monument With the Stroke of a Pen

Woodrow Wilson signed the papers creating Katmai National Monument on September 24, 1918.

The new monument protected over 1 million acres of volcanic and wilderness land around the Valley of Ten Thousand Smokes.

From the start, it was half the size of Yellowstone National Park, though only a third as big as the park is today.

The goal was to protect the extraordinary natural features and create a living laboratory for scientific research.

Most Americans didn’t even know the monument was being considered until after President Wilson signed Proclamation No. 1487 making it official.

The Valley’s Steam Vents Slowly Disappeared Over the Decades

From 1915 to 1919, Griggs’ careful observations and documentation of the fumaroles led directly to creating the Monument.

His contributions were so important that in 1956, they renamed Knife Peak Volcano as Mount Griggs in his honor.

The valley changed dramatically over time – by 1929, only a few hundred fumaroles remained, and just 10 were left by 1940 as the thermal activity cooled down.

Throughout the mid-20th century, the government expanded Katmai National Monument several times to protect salmon streams and brown bear populations.

Today, the area is known as one of the best places in the world to see Alaska brown bears, especially at Brooks Falls.

Visiting Katmai National Park and Preserve, Alaska

You can explore the Valley of Ten Thousand Smokes where Robert Griggs and National Geographic teams risked their lives studying fumaroles after the 1912 Novarupta eruption.

Take daily ranger-led bus tours from Brooks Camp via the 23-mile gravel road, with optional 3. 4-mile hikes to the valley floor.

Reserve tours through Katmailand at Brooks Lodge. Reach the park by floatplane from King Salmon or Anchorage.

No entrance fees required.

This article was created with AI assistance and human editing.

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