Illinois River Trail offers a memorable hiking experience in Tahlequah, OK. Covering 7.0 miles with 400 feet of elevation change, this moderate trail showcases Oklahoma's varied landscapes. Trail specs: 7.0 miles, 400ft elevation gain, Moderate difficulty. Type: Out-and-Back. Surface: Dirt. Time: 3 hours. Fee: Free. Dogs: Yes, on leash. Permit: No. Wildlife sightings include river otters, herons, beavers. Oklahoma's diverse ecosystems support a surprising range of species. Best times: Fall through spring; crystal clear Ozark river corridor. Gear up with sturdy footwear, plenty of water, and sun protection. Oklahoma weather can shift quickly—check forecasts before heading out. Follow Leave No Trace principles: carry out all trash, stay on marked trails, and respect wildlife and other visitors.