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Caddo Mounds


Caddoan Mounds State Historical Park, near Alto in East Texas


Caddo people occupied this site from about 800 to 1300 A.D. Archaeologists aren’t sure how many people lived at the site. They have found the remains of many houses and other structures at the site, but relatively few artifacts from many houses, indicating that these houses might have been occupied for only a short period each year.

The inhabitants of this and other sites in the region grew corn, hunted and fished, and collected wild plant foods. They traded with hunter-gatherers from Texas and adjoining regions, and appeared to share some cultural traits and traditions with the Mississippian cultures of the Midwest and Southeast, including mound building.

The Site

Caddoan Mounds today contains the remains of three large mounds. The largest, at the southern edge of the site, is called Mound A. It probably was the earliest and most significant mound. About 40 houses were built around it, but not all were in use at the same time. Mound B, near the center of the state park, probably dated to around 1100 to 1300. This rectangular platform mound measures roughly 175 feet (55 meters) north-south and 115 feet (35 meters) east-west. When in use, it would have had a flat top and broad earthen ramps on the north, east, and south sides. The northernmost mound is Mound C, which was used as a ceremonial burial mound for most of the time the site was occupied.

At least some families lived at the site year-round. Some of their houses were round and might have been as much as 60 feet in diameter.

Archaeologists have used magnetometers to map the entire site, providing a detailed map of the buried foundations of houses and other structures. They are continuing to excavate interesting structures to more accurately establish the timeline of Caddoan Mounds and to understand how the site was used.

Astronomical Significance

Like most agricultural people, the Caddo were interested in charting the seasons and watching the motions of the celestial bodies in the sky.

Many other mound sites across the Midwest and Southeast show significant astronomical alignments. At Cahokia, across the Mississippi River from St. Louis, archaeologists have discovered the foundation for a larger circle of posts, which has been nicknamed “Woodhenge” because of its astronomical connections. At the equinoxes, posts in the circle aligned with the rising Sun and Cahokia’s most important mound, which served as home for the chief. Other posts may have had similar astronomical alignments. And a site known as Serpent Mound in Ohio appears to align with sunrise and sunset on both the equinoxes and the solstices, which mark the beginning of the astronomical seasons.

Platform mounds at Caddoan Mounds likely were aligned with stars or equinoxes, according to archaeologists, although they have not yet determined the exact alignments.

Mound B, the large platform mound in the center of the site, was aligned due north-south, which indicates it was aligned with the star that marked the north celestial pole at the time. (Because Earth wobbles on its axis like a spinning top, different stars serve as the North Star at different times. The current North Star, Polaris, has served in that capacity for only a few hundred years.)

Other buildings, including large round houses built with large interior posts, also seem to have a regular orientation with respect to the north-south axis. A particular type of round house that was about 30 feet across had a large hearth in the center encircled by four square posts. These houses seem to show a regular alignment, with the posts turned a little bit west of north. Houses built by other American Indians, such as the Pawnee, were aligned with stars or other astronomical objects, and archaeologists say it’s likely that the Caddoan Mound houses were built with a similar alignment.

Public Access

Caddo Mounds State Historic Site is open to the public 8:30 a.m.-4:30 p.m. every day except Monday. The park is located on Texas 21 in Cherokee County, six miles southwest of Alto. It features an interpretive center with audio-visual presentations, plus a self-guided trail to the mounds. 1649 State Hwy 21 West, Alto 75925; (936) 858-3218.

References, Resources

Traditions of the Caddo, by George Amos Dorsey; University of Nebraska Press, 1997. Myths and folklore of the Caddo people.

Caddo Indians: Where We Come From, by Cecile Elkins Carter; University of Oklahoma Press, 1995. Written by a member of the Caddo Nation.

The Caddo Nation: Archaeological and Ethnohistoric Perspectives, by Timothy K. Perttula; University of Texas Press, 1992.

“Native Astronomy and the Plains Caddoans,” by Waldo Wedel, in Native American Astronomy, Anthony F. Aveni, editor; University of Texas Press, 1977.

Learn about...Texas Indians, by Georg Zappler; Texas Parks & Wildlife Press, 1996. A learning and activity book for children.

The Indians of Texas: From Prehistoric to Modern Times, by W.W. Newcomb Jr.; the University of Texas Press, 1961, reprinted 2002.

The Caddo Nation
Official website of the Caddo Nation in Oklahoma.

Texas Beyond History: Texas: Life and Times of the Caddo
An extensive site on Caddo history and culture.

Handbook of Texas Online: Caddo Indians


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