It's over 1500 miles from Chicago to Key West, taking a minimum of 24 hours driving without any traffic congestion, roadworks or rest/fuel stops. This route includes some toll roads: 1. Take the I-90 (Chicago Skyway/Indiana Highway) south then east to Gary, then take the I-65 south. 2. Continue south on the I-65, taking the I-465 around Indianapolis then picking up the I-65 again. 3. Follow the I-65 south, passing through Louisville , until you reach the northern outskirts of Nashville and meet the I-24. Take the I-24 south. 4. Follow the I-24 to Chattanooga to meet the I-75. Take the I-75 south. 5. You could follow the I-75 right through the middle of Atlanta but I think it's better to leave it just north of the city and take the I-285 (The Perimeter) south around the edge of the city. The I-285 meets the I-75 near Hartsfield-Jackson Atlanta International Airport. Take the I-75 south. 6. Follow the I-75, passing through or near Macon, Valdosta, Gainesville and Ocala. 7. Leave the I-75 near Wildwood (Florida) take Florida's Turnpike southeastwards. 8. Continue on Florida's Turnpike through the outskirts of Orlando then onwards, passing through or near West Palm Beach, Boca Raton and Fort Lauderdale. 9. Leave Florida's Turnpike in the northern outskirts of Miami and take the Ronald Reagan Turnpike around the city. 10. The Ronald Reagan Turnpike meets Highway 1 in Florida City. Take Highway 1 south. 11. Follow Highway 1 south, passing through or near Key Largo, Tavernierand Marathon until you reach Key West.