Indian Mountain Site (Site ID: 5BL876) facts for kids

The Indian Mountain Site (Site ID: 5BL876) is an archaeological site near Lyons, Colorado. It's an ancient campsite from the Woodland period where archaeologists have found many interesting things.

Discovering the Indian Mountain Site

The Indian Mountain Site is a special place where people lived a long time ago. It's known for its stone rings, which are circles of stones. So far, ten of these stone circles have been found. Archaeologists have fully dug up four of these rings to learn more about them.

Why This Site is Important

This site is super important because it has the oldest pottery ever found from the Plains people in Colorado. This tells us that people from the eastern plains, known as Woodland people, probably traveled to this area. They might have traded with the local people or even moved there.

Where the Site is Located

The Indian Mountain Site is found on a long, narrow ridge called a hogback. It's near Lyons, Colorado, in Boulder County, Colorado. This spot is interesting because it's where the flat plains meet the tall mountains. Because of this, the area has plants like grass, yucca, and prickly pear cactus.

Who Dug Up the Site

Guess who helped dig up the Indian Mountain Site? A group of high school students! They were part of a five-month archaeology program. These students worked with Boulder County, Colorado, during the 1983 Colorado Archaeological Awareness Year.

When the students and archaeologists explored the site, they split it into three main areas. Area 1 was the biggest, with seven stone rings. Area 2 had one ring, which was higher up than the others. Area 3 was in the far southeast part of the site and had two rings.

What Was Found at the Site

Archaeologists found many cool things at the Indian Mountain Site.

Tools and Pottery

The circular stone features found at the site were likely used to hold down the edges of ancient shelters or tents. This was a common way to build homes in Colorado, especially in the plains and foothills.

Many artifacts were also found:

• In Ring 1, they found small pieces of charcoal and two broken animal bones, likely from a deer. They also found many tiny pebbles, which suggests this area might have been a living space.
• Ring 3 had a central fireplace with rocks and charcoal.
• Inside Ring 4, two tiny pieces of pottery were discovered. When put back together, they formed a small pottery sherd about the size of a thumbnail.
• Most of the artifacts were found near Rings 4 and 5. These included flakes (sharp pieces of stone), a broken projectile point tip (like from an arrow or spear), and a special scraper tool.

In total, the excavations uncovered 60 flakes, one broken projectile point, one broken biface (a tool sharpened on both sides), a whole scraper, and the small pottery sherd.

What the Site Was Used For

Based on the stone circles, fireplaces, and animal bones, archaeologists believe the Indian Mountain Site was definitely a campsite. The pottery and scraper tool suggest that people were doing everyday activities there, like cooking and preparing food or materials.

How Old is the Site?

Archaeologists used special scientific methods to figure out how old the Indian Mountain Site is.

Radiocarbon Dating

Tiny pieces of charcoal from Rings 1, 3, and 4 were sent to the University of Arizona. Scientists used a special machine called an accelerator mass spectrometer to test them. This machine can date very small samples.

Here's what they found:

• Charcoal from Ring 1 was about 1280 years old, meaning it was used between A.D. 545 and 910.
• Charcoal from Ring 3 was about 1120 years old, used between A.D. 640 and 1050.
• Charcoal from Ring 4 was about 2140 years old, used between 410 B.C. and A.D. 25.

The very old date for Ring 4 was a surprise, especially since pottery was found there. Pottery is usually associated with later times in this region. To double-check this early date, they tried another method.

Rain Flow Dating

An archaeologist named J. F. Dormaar found a way to tell how long a rock has been in one place. Rain flowing over boulders can change the soil underneath them over time. The longer a rock sits there, the deeper it pushes down a certain layer in the soil. This method was tried at the Indian Mountain Site.

The results from this method didn't completely prove or disprove the radiocarbon dates, but they did support the early date for Ring 4. Ring 4, which had the oldest radiocarbon date, also showed the deepest changes in the soil underneath its stones. This suggests the stones had been there for a very long time.

What We Learned

While stone circle sites are common on the Plains, the Indian Mountain Site is quite unique. The discovery of the very old pottery sherd was a big surprise.

Archaeologists generally thought that Woodland culture and ideas slowly spread west into Colorado over many years. This would mean influences traveled from Kansas to Nebraska, and then finally to Colorado. Before A.D. 500, there isn't much evidence of Plains Woodland culture in Colorado. This makes the pottery found at the Indian Mountain Site very interesting!

Scientists believe that people from an eastern Woodland group likely came into contact with the people at this site. This contact could have happened in a few ways:

• A group of Woodland people might have traveled directly to the site.
• A hunting or trading party could have visited.
• The clay pot might have been traded from group to group, eventually reaching the Indian Mountain Site.
• Or, maybe an eastern potter taught the local Colorado people how to make pottery.

Right now, these are all ideas that archaeologists are still exploring. The mystery of how the pottery arrived at the site is what makes the Indian Mountain Site so fascinating!