Cook–Folsom–Peterson Expedition facts for kids

Diamond City, Montana around 1870

The Cook–Folsom–Peterson Expedition was the first organized trip to explore the amazing region that later became Yellowstone National Park. This adventure happened in 1869. It was paid for by three friends: David E. Folsom, Charles W. Cook, and William Peterson. They were from Diamond City, Montana, a gold mining town. Their stories and journals were super important. They helped inspire a bigger trip, the Washburn–Langford–Doane Expedition, which explored Yellowstone the very next year in 1870.

Exploring Yellowstone: The Journey

The three explorers left Diamond City, Montana on September 6, 1869. They traveled along the Missouri River to Three Forks, Montana. Then, they headed east through the Gallatin Valley, stopping in Bozeman, Montana for supplies.

After Bozeman, they crossed over Bozeman Pass. On September 10, 1869, they reached the Yellowstone River. They followed this river south. On September 13, 1869, they officially entered the area that would become Yellowstone National Park. This was near where the Gardner and Yellowstone rivers meet, close to today's Gardiner, Montana.

They continued their journey, exploring many famous spots:

• They saw Tower Fall.
• They explored the East Fork (now called the Lamar River) and the Lamar Valley.
• They visited the amazing Yellowstone Falls and the Grand Canyon of the Yellowstone.
• They reached the north shore of Yellowstone Lake.
• They explored the West Thumb Geyser Basin.
• They crossed the Continental Divide and found Shoshone Lake.
• Finally, they traveled down the Firehole River into the famous geyser basins, where they saw incredible hot springs and geysers.

The expedition left the park area near what is now West Yellowstone, Montana on October 3, 1869. They followed the Madison River back home. After 36 days of travel, Cook, Folsom, and Peterson returned to Diamond City, Montana, on October 11, 1869.

Key Moments of the Trip

Here are some important dates from their adventure:

• September 6, 1869: Cook, Folsom, and Peterson started their journey from Diamond City, Montana.
• September 8, 1869: They reached Bozeman, Montana, to get more supplies.
• September 13, 1869: They entered the Yellowstone park region.
• September 14, 1869: They arrived at Tower Fall and camped there for two days.
• September 21, 1869: They reached the rim of the Grand Canyon of the Yellowstone. They saw the falls from a spot now called Inspiration Point.
• September 24, 1869: They explored the north shore of Yellowstone Lake.
• September 25, 1869: They arrived at the West Thumb Geyser Basin and spent two days exploring its hot springs.
• September 29, 1869: They crossed the Continental Divide and reached Shoshone Lake.
• October 1, 1869: They saw the Great Fountain Geyser erupt in the Lower Geyser Basin.
• October 2, 1869: They saw the Excelsior Geyser erupt in the Midway Geyser Basin.
• October 11, 1869: The Cook-Folsom-Peterson team returned safely to Diamond City.

Sharing Their Amazing Story

After returning from Yellowstone, David Folsom worked as a surveyor. He and Charles Cook shared their experiences and journals with Henry D. Washburn, who was a government official. They also shared their stories with W. W. deLacy, a mapmaker. Based on their information, deLacy created a new, more accurate map of the Yellowstone region.

When the Washburn expedition went to Yellowstone in 1870, Henry D. Washburn carried copies of Cook and Folsom's diaries and deLacy's map. These were very helpful!

At first, Folsom didn't want to talk about his trip publicly. He thought people wouldn't believe his wild stories about geysers and hot springs! But his friends believed him. Their incredible tales helped inspire the bigger Washburn-Langford-Doane Expedition in 1870.

Both Cook and Folsom kept journals during their trip. Cook later combined them into one story. They tried to get it published in big newspapers, but no one believed it was real! It was finally published in a magazine called Western Monthly Magazine. Over the years, different versions of their adventure were published, showing how important their journey was. Charles Cook even lived long enough to celebrate Yellowstone's 50th birthday in 1922!

Honoring the Explorers

The Cook–Folsom–Peterson Expedition didn't officially name any of the park features that we still use today. However, later explorers and mapmakers honored them by naming some places after them:

• Folsom Peak (9,334 feet or 2,845 meters tall)
• Cook Peak (9,754 feet or 2,973 meters tall)

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