Cahokia Mounds

In 1806, President Thomas Jefferson signed legislation creating America’s first federal highway, the National Road, which stretched west from Cumberland, Maryland, reached Illinois in 1828, and carried travelers through the American Bottom and the remains of Cahokia, America’s oldest city, which had flourished more than 500 years before Jefferson’s birth. By the end of the 1800s, the road had helped spawn cities across eastern Illinois, opened western counties to settlement, and helped set the path for the St. Louis, Vandalia and Terre Haute Railroad, but westward migration and urbanization also destroyed many of Cahokia’s earthen mounds as they were plowed under or removed for fill for roads and rails. During the 20th century, archaeologists and concerned citizens worked to preserve what remained of the Cahokia complex, and in 1956 the Federal-Aid Highway Act funded archaeological surveys and artifact recovery at sites affected by federal highway construction. By 1960, plans for Interstates 55 and 70 had produced salvage archaeology that led to the discovery of Woodhenge, a finding that contributed to Cahokia Mounds being named a UNESCO World Heritage Site in 1982.

Collinsville, Illinois · United States