Pierre Martin House

North Dupo is an unincorporated community in Sugarloaf Township, St. Clair County, Illinois, United States. North Dupo is located along Illinois Route 3 south of Cahokia and north of Dupo, bordering both villages. The Pierre Martin House, which is listed on the National Register of Historic Places, is located in North Dupo.

The Cahokia Courthouse State Historic Site is a reconstructed French-Canadian structure built about 1740 at what is now 107 Elm Street, Cahokia Heights, Illinois. At various times it has served as a house and as a courthouse. It is currently interpreted to resemble its appearance about 1800 as a frontier courthouse of the Northwest Territory. The courthouse was listed on the National Register of Historic Places on November 9, 1972. The old Cahokia log home is believed to have been built in 1737 as a four-room private residence by Jean le Poincet and acquired in later years by Jean Francois Saucier, son of the designer of Fort de Chartres, from his first wife's family as her dowry. It was here that Jean Francois Saucier's six children with his first two wives, Marguerite Cadron and Angelique Lapensee were born. His other eight children with third wife Marie Francoise Nicolle were born and raised in Missouri. It is the oldest house in Illinois as well as the mid-west.

The Church of the Holy Family (French: Église de la Sainte-Famille) is a Roman Catholic church located at 116 Church Street in the St. Clair County, Illinois city of Cahokia Heights. Built beginning in 1786, it is a remarkably unaltered example of the French colonial construction style known as "poteaux-sur-solle" (post-on-sill), and one of the few such buildings surviving in North America. It was declared a National Historic Landmark and added to the National Register of Historic Places in 1970. The occupying congregation is the oldest continuously active Catholic Parish in the United States, having been founded in 1699 by Canadian missionaries, and the oldest church west of the Allegheny Mountains. At the invitation of Bishop Edward Braxton, the Institute of Christ the King Sovereign Priest continues to offer Mass in this historic church according to the Missal of 1962. Visitors are also welcome for guided tours in the summer. In celebration of the 2018 Illinois Bicentennial, Holy Family Church was selected as one of the Illinois 200 Great Places by the American Institute of Architects Illinois component (AIA Illinois).

Cahokia was a village in St. Clair County, Illinois, United States. It was located east of the Mississippi River in the Greater St. Louis metropolitan area. As of the 2010 census, 15,241 people lived in the village, a decline from 16,391 in 2000. On May 6, 2021, the village ceased to exist, being incorporated into the new city of Cahokia Heights.The name refers to one of the clans of the historic Illini confederacy, who met early French explorers to the region. Early European settlers named the nearby (and long-abandoned) Cahokia Mounds in present-day Madison County after the Illini clan. But the UNESCO World Heritage Site and State Historic Park was developed by the Mississippian culture, active here from AD 900 to AD 1500. They created an extensive urban complex, the largest of the farflung Mississippian culture territory through the Mississippi and Ohio river valleys. French Canadian colonists founded Cahokia village in 1696 as a Catholic mission. The historic Church of the Holy Family is the oldest continually active Catholic parish in the United States, as well as the oldest church west of the Allegheny Mountains. Other significant colonial and Federal-period buildings listed on the National Register of Historic Places include the Cahokia Courthouse (c. 1740, in the French Colonial style); and the Jarrot Mansion (c. 1810).

The Nicholas Jarrot Mansion is a historic house at 124 East First Street in Cahokia Heights, Illinois and is operated as an inactive historic site by the Illinois Historic Preservation Agency (IHPA). It is a State Historic Site, is listed on the National Register of Historic Places, and became a National Historic Landmark in 2001. Built in 1807–1810 for the son of French colonists, it is an extremely rare example of Federal architecture in the upper Mississippi River valley.

Cahokia Heights is a city in St. Clair County, Illinois, United States. It was founded on May 6, 2021, by the merger of the villages of Cahokia and Alorton and the city of Centreville. On May 6, 2021, Curtis McCall Sr. was sworn in as the city's first mayor, having run unopposed.

Dupo is a village in St. Clair County, Illinois, United States. The population was 4,138 at the 2010 census, an increase from 3,933 in 2000. The village was settled in about 1750 and was incorporated in 1907. Its modern name, adopted in the early 20th century, is shortened from Prairie du Pont ("Bridge Prairie").

East Carondelet is a village in St. Clair County, Illinois, United States. The population was 499 as of the 2010 census.

Cahokia High School is a public high school in Cahokia Heights, Illinois, United States that is part of the Cahokia Unit School District 187.

Sugarloaf Township is located in St. Clair County, Illinois. As of the 2010 census, its population was 7,322 and it contained 3,219 housing units.

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 the last remaining of the mounds built within present-day St. Louis by a Native American culture that thrived in the area from A.D. 600-1300. It is the oldest human-made structure in the city of St. Louis.

The Greater Saint Louis Air & Space Museum is a museum with the mission to preserve and display historic air and space craft and artifacts, and provide educational programs.