Merrimac, Illinois

The Meramec River (), sometimes spelled Maramec River (the original US mapping spelled it Maramec but later changed it to Meramec), is one of the longest free-flowing waterways in the U.S. state of Missouri, draining 3,980 square miles (10,300 km2) while wandering 218 miles (351 km) from headwaters southeast of Salem to where it empties into the Mississippi River near St. Louis at Arnold and Oakville. The Meramec watershed covers six Missouri Ozark Highland counties—Dent, Phelps, Crawford, Franklin, Jefferson, and St. Louis—and portions of eight others—Maries, Gasconade, Iron, Washington, Reynolds, St. Francois, Ste. Genevieve, and Texas. Between its source and its mouth, it falls 1,025 feet (312 m). Year-round navigability begins above Maramec Spring, just south of St. James. The Meramec's size increases at the confluence of the Dry Fork, and its navigability continues until the river enters the Mississippi at Arnold, Missouri.

Imperial is a census-designated place (CDP) in Jefferson County, Missouri, United States, and is a suburb of St. Louis. The population was 4,947 at the 2020 census. Imperial was originally known as West Kimmswick, the historic Catholic church of St. John’s in Imperial, became an independent parish in 1869.

Windsor Harbor Road Bridge is a historic Pratt through truss bridge located at Kimmswick, Jefferson County, Missouri. It was built in 1874-1875 by the Keystone Bridge Company; the bridge was dismantled and re-erected at its present site in 1930. It measures 20.3 feet (6.2 m) wide and the span is 123.3 feet (37.6 m).: 2 It was listed on the National Register of Historic Places in 1983.A sign outside the bridge states:

Kimmswick Historic District is a historic national historic district located at Kimmswick, Jefferson County, Missouri. The district encompasses 44 contributing buildings, 1 contributing site, and 1 contributing structure in the central business district and surrounding residential sections of Kimmswick. It developed between about 1859 and 1940 and includes representative examples of Bungalow / American Craftsman style architecture. Notable buildings include the Barbagallo House (c. 1850), Bernard Klein House (c. 1865), Horninghauser House (c. 1865), Franz A Hermann / John O'Heim House and Brewery (c. 1859), Kimmswick Post Office (1914), Martin Meyer Building (c. 1880), The Old Market (c. 1877), Rauschenbach Building (1884), Phillip Meyer Building (c. 1875), Ambrose Ziegler House (c. 1925), and Kimmswick City Hall (c. 1903).It was listed on the National Register of Historic Places in 2007.

Kimmswick is a city in Jefferson County, Missouri, United States. The population was 157 at the 2010 census.

Windsor High School is a public high school in Imperial, Missouri, and is part of the Windsor C-1 School District.

The American Bottom is the flood plain of the Mississippi River in the Metro-East region of Southern Illinois, extending from Alton, Illinois, south to the Kaskaskia River. It is also sometimes called "American Bottoms". The area is about 175 square miles (450 km2), mostly protected from flooding in the 21st century by a levee and drainage canal system. Immediately across the river from St. Louis, Missouri, are industrial and urban areas, but nearby marshland, swamps, and the Horseshoe Lake (which was created by the river) are reminders of the Bottoms' riparian nature. This plain with its rich alluvial soil, served as the center for the pre-Columbian Cahokia Mounds civilization, and later the French settlement of Illinois Country. Deforestation of the river banks in the 19th century to fuel steamboats had dramatic environmental effects in this region. The Mississippi River between St. Louis and the confluence with the Ohio River became wider and more shallow, as unstable banks collapsed into the water. This resulted in more severe flooding and lateral changes of the major channel, causing the destruction of several French colonial towns, such as Kaskaskia, which relocated; Cahokia, and St. Philippe, Illinois. The southern portion of the American Bottoms is primarily agricultural, planted chiefly in corn, wheat, and soybean. The American Bottom is part of the Mississippi Flyway used by migrating birds and has the greatest concentration of bird species in Illinois. The flood plain is bounded on the east by a nearly continuous, 200- to 300-foot high, 80-mile (130 km) long bluff of limestone and dolomite, above which begins the great prairie that covers most of the state. The Mississippi River bounds the Bottom on its west, and the river abuts the bluffline on the Missouri side. Portions of St. Clair, Madison, Monroe, and Randolph counties are in the American Bottom. Its maximum width is about 9 miles (14 km) in the north, and it is about 2 to 3 miles in width throughout most of its southern extent.

Sulphur Springs is an unincorporated community in eastern Jefferson County, Missouri, United States. It is located near Barnhart, bordering the banks of Glaize Creek and the Mississippi River. Sulphur Springs was platted in 1860, and named for a sulphur spring near the original town site. A post office was established at Sulphur Springs in 1837, and remained in operation until 1990.On August 5, 1922, at Sulphur Springs, two trains collided on the Iron Mountain Railroad tracks, resulting in 34 people killed and 150 injured in the largest train accident in Missouri history.

Mastodon State Historic Site is a publicly owned, 431-acre (174 ha) archaeological and paleontological site with recreational features in Imperial, Missouri, maintained by the Missouri Department of Natural Resources, preserving the Kimmswick Bone Bed. Bones of mastodons and other now-extinct animals were first found here in the early 19th century. The area gained fame as one of the most extensive Pleistocene ice age deposits in the country and attracted scientific interest worldwide. The site was purchased by the state in 1976 following an effort to preserve it from destruction with the construction of Interstate 55. Archaeological history was made at the site in 1979 when scientists excavated a stone spear point made by hunters of the Clovis culture (14,000–10,000 years ago) in direct association with mastodon bones. This was the first solid evidence of the coexistence of people and these giant prehistoric beasts. The Kimmswick Bone Bed was added to the National Register of Historic Places in 1980.

Arnold is a city in Jefferson County Missouri, United States and is also a suburb of St. Louis. The population was 20,858 at the 2020 United States Census.

Valmeyer is a village in Monroe County, Illinois, United States. The population was 1,233 at the 2020 census. It was originally located in the American Bottom floodplain of the Mississippi River but now occupies higher land to the east.

Oakville is a census-designated place (CDP) in south St. Louis County, Missouri, United States. The population was 36,301 at the 2020 census. Oakville is 18 miles south of the city of St. Louis and borders the Mississippi and Meramec rivers; the area is part of "South County" (south St. Louis County).