Cahokia Mounds State Historic Site, located in the Saint Louis Metro East region of Illinois, was home to the largest prehistoric city north of Mexico. The city was occupied for seven centuries as the American Indians here farmed, traded, created art, studied the sun, and built massive earthen mounds. Between 15,000 and 20,000 people lived at Cahokia when it reached its peak 800 years ago. Today, Cahokia is a UNESCO World Heritage Site. You can walk the grounds where the Indians walked, climb to the top of a 100 ft (30 m) mound, and visit a world-class museum to learn more about life in this part of America before Columbus.
The main features of the site are the 69 remaining man-made mounds, the largest of which is Monks Mound, around 100 ft (30 m) tall. The rest of the 2,200 acre (890 hectare) site consists of many grass covered mounds that vary in size and shape, several interpretive trails and signage, a reconstruction of the Woodhenge sun calendar, and reconstructions of the palisade/stockade walls.
Built by Mississippian Indians between 600 and 1300 AD, Cahokia was the largest prehistoric city in all of what became the United States. Then covering six sq mi (16 sq km), Cahokia was a melting pot of Indian groups. The city included large fields of corn, wooden houses for thousands of people, grand open plazas, and about 120 earthen mounds.
Though the city was abandoned in the 1300's, French and later American settlers arrived in the 17th and 18th century and again began growing crops. Even in the early 1800's, archeologists recognized that there was something unique here, but the land continued to be used for farming for the next 125 years. In the 1930's, the United States government considered making the site into a national park, but ultimately decided against the idea. The state of Illinois then purchased an initial plot of land including Monks Mound, and continues to expand and operate the park today through the Illinois Historic Preservation Agency. Cahokia Mounds State Historic Site remains one of the few World Heritage sites in the United States which is not run by the federal government.
Cahokia Mounds was designated a National Historic Landmark in 1964, listed on the National Register of Historic Places in 1966, and named a World Heritage Site by the United Nations in 1982.
Cahokia Mounds is in the Mid-Western Plains a few miles from the banks of the Mississippi River in the ridge and swale floodplain known as the "American Bottom." This area included numerous lakes, sloughs, marshes and streams, many of which formed in the old abandoned river channels. Bottomland forests dominated around the water sources. Today, cities have built up throughout the American Bottom, but this 2,200 acre (9 km2) oasis gives an idea of how the lands may have appeared long ago.
Check the weather forecast for Collinsville from NOAA.
The Mississippi River makes this area humid, though temperatures are generally moderate. Storms can occur at any time of the year. July and August are hottest and most humid, and January and February are cold, with occasional snow. Normal temperatures range from 21°F in the winter to 90°F in the summer (-6°C to 32°C), but summer highs of 100°F and winter lows of 0°F are not uncommon (38°C and -18°C).
Despite the similarity in name, Cahokia Mounds is not in the city of Cahokia, but is located in Collinsville, Illinois, about ten miles (16 km) away. The park entrance is on Collinsville Rd in Collinsville, about 8 mi (12 km) from downtown St Louis. The park is located just off of Interstate 55, and not far from Historic Route 66.
From St. Louis or West St. Louis County: Take Interstate 55/70, 64 or Highway 40 & 44 across the Poplar St. Bridge into Illinois. Follow I-55/70, not 64, to Exit 6 (Highway 111). Exit and turn right onto Highway 111 south. At traffic signal turn left onto Collinsville Rd. The Interpretive Center is about 1.5 mi (2.5 km) on the right.
From North St. Louis County: Take I-270 East into Illinois to I-255. Take I-255 South (Memphis) to Exit 24, Collinsville Rd. Exit and turn left onto Collinsville Rd at the stoplight at the end of the off-ramp. The Interpretive Center is about 1.5 mi (2.5 km) on the left.
From South St. Louis County: Take I-255 across the Jefferson Barracks Bridge into Illinois. Continue on I-255 until Exit 24, Collinsville Rd. Exit and turn left onto Collinsville Rd at the stoplight at the end of the off-ramp. The Interpretive Center is about 1.5 mi (2.5 km) on the left.
From Northern and Eastern Illinois via I-55/70: Take I-55 South or I-70 West to the I-255 exit 10, just past Collinsville. Take I-255 South (Memphis) to the next Exit (24) at Collinsville Rd. Exit and turn left onto Collinsville Rd at the stoplight at the end of the off-ramp. The Interpretive Center is about 1.5 mi (2.5 km) on the left.
From Eastern Illinois via I-64: Take I-64 to I-255 North. Take I-255 North to Exit 24, Collinsville Rd. Exit and turn left onto Collinsville Rd at the stoplight at the end of the off-ramp. The Interpretive Center is about 1.5 mi (2.5 km) on the left.
From Southern Illinois: Take I-255 North to Exit 24, Collinsville Rd. Exit and turn left onto Collinsville Rd at the stoplight at the end of the off-ramp. The Interpretive Center is about 1.5 mi (2.5 km) on the left.
From Lambert St Louis International Airport: (22 Miles) Take I-70 East. After crossing the Mississippi River on the Poplar St Bridge, follow I-55/70 to Exit 6 (Highway 111). Exit and turn right onto Highway 111 south. At traffic signal turn left onto Collinsville Rd. The Interpretive Center is about 1.5 mi (2.5 km) on the right.
Bi-State Bus: Recent cutbacks in bus service have eliminated the Cahokia Mounds stop. With the nearest bus stop now four mi (6 km) from the park, there is no easy way to go to Cahokia Mounds by bus. (Bi-State serves St. Louis and parts of Illinois)
Madison County Transit Bus: MCT bus #18 stops at Black Lane and Collinsville Rd. This is about .75 mi (1.2 km) west of the site. There are no sidewalks to reach the site.
MetroLink, St. Louis's public transit light rail system, can take you to the Emerson Park Station in East St. Louis. However, you'll still be about 8 mi (13 km) from Cahokia Mounds. You'll need to complete your trip by taxi.
Interpretive Center. 9AM-5PM. The starting point for your visit to Cahokia Mounds, the Interpretive Center has a very good introductory video to help make sense of the site. There are also displays of the finds and a recreated life-size portion of a village with houses and mannequins involved in daily activities. Volunteers are available to help explain what is known of the civilization which lived here 1,000 years ago.free, donations accepted. edit
Monks Mound. 8AM-dusk. The largest prehistoric earthen-work in the New World provides nice views over the whole historic site. An easy 154 steps will take you to the top of the 100 ft (30 m) mound, where you can see central St Louis including the impressive Gateway Arch about 7 mi (11 km) away. Completely man-made, Monks Mound contains 22 million cubic feet (625,000 m3) of dirt. If it were made of ice cream, it would be large enough to give every person in the United States a half gallon.free. edit
Woodhenge. 8AM-dusk. About one-half mi (1 km) west of Monks Mound, you will see a large circle of 48 wooden posts, over 400 ft (125 m) in diameter. It has been reconstructed in its original location and is a solar calendar, with posts aligning with the equinox and solstice sunrises.Free. edit
Contemporary Indian Art Show. In early July, several dozen Indian artists gather at Cahokia to show their creative abilities in sculpture, pottery, jewelry, painting, and other arts. They talk about their work and offer it for sale. Prices range from a couple of dollars to several tens of thousands. With the Indian artist present, buyers know that they are purchasing genuine native American works. Indian market weekends in March and November feature fewer artists but additional chances to view and purchase Indian art.Free admission. edit
North American Indian Photography Contest. Each fall, amateurs and professionals submit photographs on any subject dealing with American Indians. Winning entries are announced and cash prizes awarded in mid-October. Entries generally remain on display in the Interpretive Center for a couple of months.Free admission. edit
Winter Lecture Series. Each winter, talks by noted archeologists describe current work being done in other parts of the country or the world.Free. edit
Public Tours. During June, July, and August public one hour tours are conducted Monday through Saturday at 10:30AM and 2:30PM, and Sunday at 12:30PM and 2:30PM. The early tour visits the Stockade reconstruction and goes up Monks Mound. The later tour goes through the Grand Plaza to the Twin Mounds and Mound 72. During April, May, September, and October public tours are conducted on Saturdays and Sundays at 2:30PM. No public outdoor tours Nov-Mar. No reservations are needed. Free. edit
iPod audio-visual tours. iPods are available for rental in the Museum Shop. These are loaded with three outside tour trails (Grand Plaza, Monks Mound, Woodhenge) and a tour through the exhibit gallery in the Interpretive Center. Adult and child versions of each tour are included on the iPod. Available in English, German, and Spanish.$5. edit
Walk the site. In any season of the year, the grounds of the site are open to walk from 8AM to dusk. You may borrow a self-paced audio-cassette tour (free) or purchase a guidebook ($1) to explain and highlight what you are seeing.edit
Geocaching. Geocaching is a sort of scavenger hunt using a GPS receiver to locate the hidden item. Several geocaches in the park have been created with official permission.edit
The most-popular tours are Grand Plaza and Monks Mound. These are well-marked, follow cement paths, and take about 30-45 minutes each. They have audio guides, iPod guides, printed guides, and human tour guides to help you understand the site.
In addition, there are several other defined trails with trail markers and printed guides.
Nature/Culture Hike. This 6.2 mi (10 km) hike explores more remote parts of the site.edit
Marsh Walk. This 1 mi (1.5 km) hike circles Spring Lake and passes a fresh-water marsh.edit
Prairie For the Praire State Nature Walk. This 1 mi (1.5 km) hike shows the flora and fauna of the prairie.edit
Ten Mile Trail. This 10 mi (16 km) hike takes you through many parts of the site.edit
Many activities are scheduled each year. While some are unique one-time events, others are repeated every year. A detailed calendar of upcoming events is available on the web. 
Sunrise at Woodhenge. On the Sunday morning closest to the solar equinox (Mar and Sep) or the solar solstice (Jun and Dec), early-risers gather to watch the sun line up with the wooden posts of Woodhenge. As the sun breaks over the horizon, an archeologist is on hand to explain how the massive solar calendar worked.Free. edit
Nature/Culture hike. Twice a year (May and Sep) a special walking tour takes visitors through some of the usually-unseen parts of the site. Normally conducted by an archeologist and author who has worked at Cahokia for over 35 years, the three hour tour is considered the best opportunity to really learn about Cahokia and its past. The group is also accompanied by a naturalist who points out which plants are native to the area and how they were used in prehistoric times.Free. edit
Kids Day. Each May, Kids Day provides hands-on activities for all ages, including crafts, games, dancing. Try your hand at using an Atlatl to throw a spear, as it was done before the bow and arrow were invented.Free. edit
Archeology Day. Each August, Archeology Day provides a chance to meet real archeologists, tour the summer excavations, touch prehistoric artifacts. The day also includes hands-on activities for all ages, including crafts, games, dancing. Try your hand at rolling a chunky stone and playing other prehistoric games.Free. edit
Excavations. Each summer, several archeological digs are conducted at Cahokia. While they are underway, visitors are invited to tour the dig sites and talk with the people doing the work.Free. edit
Join an excavation, ☎ +1 618 346-5160. If you would like to volunteer to participate in one of the summer excavations, complete an application in the early spring. Volunteers may work for just a few days or several weeks. Throughout the year, volunteers assist in lab work such as washing, labeling, packaging, and inventorying archaeological artifact collections. Contact the Visitors Center for an application.Free. edit
Gift Shop, ☎ 1 618 344-9221, . 9AM-4:45PM. The Gift Shop in the Visitor's Center has an excellent selection of books dealing with archaeology, Cahokia, and American Indians, as well as Indian-made jewelry, pottery, baskets, and much more.edit
Ticks and poison ivy can be found on some of the longer trails. Wear long pants and use insect spray for protection.
While the most popular trails are cement pathways, segments of some trails are made of dirt, woodchips, grass, or gravel. Wheelchair users should ask about the specific trail they are using before setting out. For the longer trails, hiking shoes are recommended.
As an archeological site, unauthorized digging for any reason in any area is strictly illegal. Do not add an unauthorized geocache, dig for artifacts, or pull out plants as you move about the site. It is unlawful to disturb or remove flora, fauna, or artifacts from the site.
Mastodon State Historic Site, 1050 Charles J Becker Dr., Imperial, MO (I-255 South. Cross the Mississippi River to Missouri and take I-55 South, to Imperial Main Street Exit #186.), ☎ 1 636 464-2976, . While 37 mi (60 km) from Cahokia Mounds, this park takes your prehistoric journey even further back in time. The discovery of Clovis spear points and Mastodon bones at this site was the first proof that man existed at the same time as the Mastodon. The museum helps you understand how man lived some 14,000 years ago.edit
Lewis and Clark State Historic Site, One Lewis and Clark Trail, Hartford IL, ☎ 1 618 251-5811, . Just 12 mi (19 km) from the site of the largest prehistoric city in America, Lewis and Clark spent the winter of 1803-04 gathering men and supplies and planning their trip west. At 3PM on May 14, 1804 they set out from this spot to explore the west. The museum includes a 55 ft long full-size replica of their keelboat and an outdoor reconstruction of Camp River Dubois.edit
Catsup Bottle Water Tower, 800 S Morrison Ave, . Collinsville is home to the world's largest catsup bottle. At 170 ft (50 m) tall, it would hold 100,000 gallons of catsup, or water.free. edit
National Great Rivers Museum, #2 Locks and Dam Way, Alton, IL, ☎ 1 618 462-6979. 9AM-5PM. The story of the Mississippi River and its impact on America, from prehistoric times to today, is told 20 minutes up the road in Alton. Operated by the US Army Corps of Engineers. Three times a day, you can tour the giant Melvin Price Locks and Dam which span the Mississippi, and watch barges and boats rise or fall in the locks to continue their trip along the river.free. edit
If you are looking for additional activities, St Louis is filled with attractions and destinations, and is only 8 mi (13 km) away. The city includes Eero Saarinen's impressive Gateway Arch, the Anheuser Busch Budweiser Brewery, the St. Louis Art Museum, Zoo, History Museum, Science Center, City Museum, Magic House, professional baseball, football, and hockey teams, and much more.
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