Vandalia  is a city in Central Illinois. The town where Abraham Lincoln began his political career, Vandalia was the state capital of Illinois from 1820 to 1839. As a member of the state legislature, in 1837 Lincoln made his first comments against slavery in Vandalia.
The state capital moved to Vandalia only two years after Illinois became a state. Three separate buildings in Vandalia served as the Capitol: the first burned, the second was torn down, and the third remains as a historic site, maintained both as a part of Illinois history, and more importantly as a part of the life of Abraham Lincoln. In 1839, the legislature moved to Springfield, leaving the quiet town of Vandalia behind.
Long before the Interstate Highway system, the US federal government began building the National Road in 1811, planned to connect Maryland with Missouri. This was the first federally-funded road in the new country. While funding shortfalls stopped the road in Vandalia in 1839, the National Road served as the gateway to the west for thousands of settlers, bringing them as far as central Illinois. When the "modern" US highway system was developed in 1925, the National Road became a part of US 40.
Today, you may tour the last Vandalia State Capitol, sit in the chamber where Lincoln sat, visit the National Road Interpretive Center, and see Lincoln-era artifacts and antiques at the county museum.
Vandalia is on Interstate 70, between St. Louis and Indianapolis. US Highway 40 goes through the center of town.