Monks Mound is the largest
Pre-Columbian
In the history of the Americas, the pre-Columbian era spans from the original settlement of North and South America in the Upper Paleolithic period through European colonization, which began with Christopher Columbus's voyage of 1492. Usually, ...
earthwork in the Americas and the largest pyramid north of
Mesoamerica
Mesoamerica is a historical region and cultural area in southern North America and most of Central America. It extends from approximately central Mexico through Belize, Guatemala, El Salvador, Honduras, Nicaragua, and northern Costa Rica ...
. The beginning of its construction dates from 900–955 CE. Located at the
Cahokia Mounds
The Cahokia Mounds State Historic Site ( 11 MS 2) is the site of a pre-Columbian Native American city (which existed 1050–1350 CE) directly across the Mississippi River from modern St. Louis, Missouri. This historic park lies in south- ...
UNESCO World Heritage Site
A World Heritage Site is a landmark or area with legal protection by an international convention administered by the United Nations Educational, Scientific and Cultural Organization (UNESCO). World Heritage Sites are designated by UNESCO for ...
near
Collinsville, Illinois
Collinsville is a city located mainly in Madison County, and partially in St. Clair County, Illinois. As of the 2010 census, the city had a population of 25,579, an increase from 24,707 in 2000. Collinsville is approximately from St. Louis, Mi ...
, the mound size was calculated in 1988 as about 100 feet (30 m) high, 955 feet (291 m) long including the access ramp at the southern end, and 775 feet (236 m) wide. This makes Monks Mound roughly the same size at its base as the
Great Pyramid of Giza
The Great Pyramid of Giza is the biggest Egyptian pyramid and the tomb of Fourth Dynasty pharaoh Khufu. Built in the early 26th century BC during a period of around 27 years, the pyramid is the oldest of the Seven Wonders of the Ancient Worl ...
(13.1 acres / 5.3 hectares). The perimeter of its base is larger than the
Pyramid of the Sun
The Pyramid of the Sun is the largest building in Teotihuacan, and one of the largest in Mesoamerica. It is believed to have been constructed about 200 AD. Found along the Avenue of the Dead, in between the Pyramid of the Moon and the Ciudadel ...
at
Teotihuacan
Teotihuacan (Spanish: ''Teotihuacán'') (; ) is an ancient Mesoamerican city located in a sub-valley of the Valley of Mexico, which is located in the State of Mexico, northeast of modern-day Mexico City. Teotihuacan is known today as t ...
. As a platform mound, the earthwork supported a wooden structure on the summit.
Unlike
Egyptian pyramids which were built of stone, the
platform mound
Platform may refer to:
Technology
* Computing platform, a framework on which applications may be run
* Platform game, a genre of video games
* Car platform, a set of components shared by several vehicle models
* Weapons platform, a system or ...
was constructed almost entirely of layers of basket-transported soil and clay. Because of this construction and its flattened top, over the years, it has retained rainwater within the structure. This has caused
slumping, the avalanche-like sliding of large sections of the sides at the highest part of the mound. Its designed dimensions would have been significantly smaller than its present extent, but recent excavations have revealed that slumping was a problem even while the mound was being made.
[Iseminger, Bill et al]
"Monks Mound (Mound 38) Projects 1997 – 2007
, from ''The Cahokian'' (various issues 1998–2007)- at cahokiamounds.com
Construction and abandonment
![Cahokia monks mound HRoe 2008](https://upload.wikimedia.org/wikipedia/commons/2/2a/Cahokia_monks_mound_HRoe_2008.jpg)
Construction of Monks Mound by the
Mississippian culture began about 900–950 CE, on a site that had already been occupied by buildings. The original concept seems to have been a much smaller
mound
A mound is a heaped pile of earth, gravel, sand, rocks, or debris. Most commonly, mounds are earthen formations such as hills and mountains, particularly if they appear artificial. A mound may be any rounded area of topographically higher ...
, now buried deep within the northern end of the present structure. At the northern end of the summit plateau, as finally completed around 1100 CE, is an area raised slightly higher still, on which was placed a building over long, the largest in the entire Cahokia Mounds urban zone. Botanical remains from Monks Mound suggest it was built much more quickly than previously thought, perhaps on the order of several consecutive decades, providing an alternative view of its construction history. Deep excavations in 2007 confirmed findings from earlier test borings, that several types of earth and
clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4).
Clays develop plasticity when wet, due to a molecular film of water surrounding the clay par ...
from different sources had been used successively.
Study of various sites suggests that the stability of the mound was improved by the incorporation of bulwarks, some made of clay, others of sods from the Mississippi flood-plain, which permitted steeper slopes than the use of earth alone. The structure rises in four terraces to a height of with a rectangular base covering nearly and containing 22 million cubic feet of adobe, carried basket by basket to the site.
The most recent section of the mound, added some time before 1200 CE, is the lower terrace at the south end, which was added after the northern end had reached its full height. It may partly have been intended to help minimize the slumping which by then was already under way. Today, the western half of the summit plateau is significantly lower than the eastern; this is the result of massive slumping, beginning about 1200 CE. This also caused the west end of the big building to collapse. It may have led to the abandonment of the mound's high status, following which various wooden buildings were erected on the south terrace, and garbage was dumped at the foot of the mound. By about 1300, the urban society at Cahokia Mounds was in serious decline. When the eastern side of the mound started to suffer serious slumping, it was not repaired.
European settlers
There is no evidence of significant Native American settlement in the Cahokia Mounds urban area for hundreds of years after about 1400 CE. In 1735,
French missionaries built a chapel at the west end of the south terrace of the mound. The River L'Abbe Mission served a small
Illiniwek
The Illinois Confederation, also referred to as the Illiniwek or Illini, were made up of 12 to 13 tribes who lived in the Mississippi River Valley. Eventually member tribes occupied an area reaching from Lake Michicigao (Michigan) to Iowa, Ill ...
community, until they were forced to abandon the area by rival tribes about 1752. In 1776, during the
American Revolutionary War
The American Revolutionary War (April 19, 1775 – September 3, 1783), also known as the Revolutionary War or American War of Independence, was a major war of the American Revolution. Widely considered as the war that secured the independence of t ...
, a
trading post
A trading post, trading station, or trading house, also known as a factory, is an establishment or settlement where goods and services could be traded.
Typically the location of the trading post would allow people from one geographic area to tr ...
called the Cantine was established next to the mound (by then known as the Great Nobb). It lasted only until 1784.
In the early 19th century, the land was claimed by people of French descent, and Nicholas Jarrot had a deed for most of it. He donated some to a small group of French
Trappist
The Trappists, officially known as the Order of Cistercians of the Strict Observance ( la, Ordo Cisterciensis Strictioris Observantiae, abbreviated as OCSO) and originally named the Order of Reformed Cistercians of Our Lady of La Trappe, are a ...
monks, who settled on one of the smaller mounds from 1809. They took advantage of the big mound's terraces to grow produce, which was elevated above the danger of flooding: wheat on the upper levels, garden produce on the south terrace. During their short stay in the area, which lasted until 1813,
Henry Brackenridge
Henry Marie Brackenridge (May 11, 1786 – January 18, 1871) was an American writer, lawyer, judge, superintendent, and U.S. Congressman from Pennsylvania.
Born in Pittsburgh in 1786, he was educated by his father, the writer and judge Hugh ...
visited the site and published the first detailed description of the largest mound. He named it Monks Mound.
In 1831 T. Amos Hill bought the plot including the Mound. He built a house on the upper terrace, and sank a well. This work revealed various archaeological remains, including human bones.
[John A. Walthall & Elizabeth D. Benchley, "The River L'Abbé Mission: A French Colonial Church for the Cahokia Illini on Monks Mound"](_blank)
''Studies in Illinois Archaeology'', No. 2, Springfield, IL: Historic Preservation Agency (1987), via archive.org
Archaeology
![Atop-monks-mound](https://upload.wikimedia.org/wikipedia/commons/3/3f/Atop-monks-mound.JPG)
Thomas I. Ramey, who bought the site in 1864, began an era of more responsible ownership, and encouraged archaeological investigation. Many artifacts were found at or near the surface. Ramey had a tunnel made nearly into the north face of the mound, but it revealed nothing of historic interest. By this time, people were beginning to consider the mound more within its context. A survey made for local dentist Dr. John R. Patrick in the 1880s marked the beginning of modern understanding of the Cahokia site as a whole, and its relationship to other sites in the area.
Many archaeological investigations of the mound have taken place since then. One of the biggest began in the 1960s, when Nelson Reed, a local businessman and historian of native cultures, obtained permission to conduct excavations. He was trying to locate the high-status building (temple or palace) presumed to have stood at the peak of Monks Mound. By drilling cores at various points on the mound, his team revealed the various stages of its construction from the 10th to 12th centuries CE. Remains of a fairly recent house (presumably Hill's) were found, but no temple.
In 1970 Reed returned to work at the mound, and adopted a new strategy: scraping away the topsoil from several patches with a
backhoe, to a depth of around . This quickly revealed various features, including what appeared to be the outline of the temple. Further backhoe work in 1971 confirmed the shape of the presumed temple at over long, the largest building found at Cahokia. This technique was opposed by professional archaeologists because it destroyed several hundred years of
stratification
Stratification may refer to:
Mathematics
* Stratification (mathematics), any consistent assignment of numbers to predicate symbols
* Data stratification in statistics
Earth sciences
* Stable and unstable stratification
* Stratification, or st ...
over most of the mound's summit, which was the evidence by which they could place and evaluate artifacts and construction. Reed's backhoe excavations revealed other significant features, such as a hole which seemed to have been the socket for a post about three feet (one metre) in diameter. The dramatic finds encouraged the Governor of Illinois to budget for an expansion of the Cahokia Mounds State Park.
Preservation
From the time the original urban society collapsed, the great mound became overgrown with trees, the roots of which helped stabilize its steep slopes. In the 20th century, researchers removed the trees in the course of work at the mound and park preparation. Reduction of groundwater levels in the Mississippi floodplain during the 1950s caused the mound to dry out, damaging the clay layers within. When heavy rainfall occurred, it caused new slumping, starting about 1956. The increasingly violent weather of recent decades has exacerbated the problem. In 1984-5 there were several slumps, and the state government brought in surplus soil to make repairs to the major scar on the eastern side. A decade later, there was further slumping on the western side, so irregular that repair was impractical. Drains were installed to reduce the effects of heavy rain. It was during this process that workers discovered a mass of stone deep within the mound.
The repairs of the 1980s and 1990s were only partly successful. In 2004-5 more serious slumping episodes occurred. These demonstrated that adding new earth to repair the major slump on the east side had been a mistake. Experts decided to take a new approach. In 2007, backhoes were used to dig out the entire mass of earth from this slump and another at the northwest corner, to a level beyond the internal slippage zone. Engineers created a series of anti-slip "steps" across the exposed face before the original earth (minus the imported repair material) was replaced at its original level. To avoid introducing water deep into the mound's interior, the work was carried out in high summer, and as quickly as possible. In parallel with the repair work, teams of archaeologists studied the evidence that was being revealed.
The eastern sliding zone penetrated more deeply within the mound than originally estimated, and the excavation had to be very large-
[Bostrom, Peter A]
Mound repair: Cahokia Mounds
(31 Jul 2007)- summary with photos 50 feet (16 m) wide, to a height of 65 feet (20 m) above the mound base.
This heightened concerns about a conflict between conservation and archaeology.
See also
*
List of Mississippian sites
This is a list of Mississippian sites. The Mississippian culture was a mound-building Native American culture that flourished in what is now the Midwestern, inland- Eastern, and Southeastern United States from approximately 800 CE to 1500 C ...
*
Mound 34
*
Mound 72
Mound 72 is a small ridgetop mound located roughly to the south of Monks Mound at Cahokia Mounds near Collinsville, Illinois. Early in the site's history, the location began as a circle of 48 large wooden posts known as a "woodhenge". The woodhe ...
*
Southeastern Ceremonial Complex
The Southeastern Ceremonial Complex (formerly the Southern Cult), aka S.E.C.C., is the name given to the regional stylistic similarity of artifacts, iconography, ceremonies, and mythology of the Mississippian culture. It coincided with their ado ...
*
Sugarloaf Mound
Sugarloaf Mound is the sole remaining Mississippian culture platform mound in St. Louis, Missouri, a city commonly referred to in its earlier years as "Mound City" for its approximately 40 Native American earthen structures.
Sugarloaf Mound is t ...
References
Further reading
* Price, Douglas T. and Gary M. Feinman. ''Images of the Past, 5th ed.'' New York: McGraw-Hill (2008) . pp. 282–285.
"The Trappists of Monk's Mound" — ''Illinois Catholic Historical Review'', 8:106‑136 (1925)
External links
Monks Mound (Mound 38) Cahokia Mounds State Historic Site website.
UNESCO – Cahokia Mounds State Historic Site2016 discussion of new research indicating construction in as little as twenty years
{{Authority control
Buildings and structures completed in 1100
11th-century establishments in North America
1809 archaeological discoveries
Middle Mississippian culture
Archaeological sites in Illinois
Protected areas of Madison County, Illinois
Mounds in Illinois
Pyramids in the United States
Cahokia