Giveaway Reminder!! Guess our Spring Jam artist correctly and you could win one of many cool prizes! Here's a hint. The Top 8 Longest Rivers in Illinois are: 1. Mississippi River 2. Ohio River 3. Wabash River 4. Kaskaskia River 5. Rock River 6. Illinois River 7. Sangamon River 8. Little Wabash River #UIUCSpringJam23