Carbondale is a city in Jackson County, Illinois, United States, within the Southern Illinois region informally known as "Little Egypt." The city developed from 1853 because of the stimulation of railroad construction into the area. Today the major roadways of Illinois Route 13 and U.S. Route 51 intersect in the city. The city is southeast of St. Louis, Missouri, on the northern edge of the Shawnee National Forest. Carbondale is the home of the main campus of Southern Illinois University (SIU).