Wow - unexpected with hills, scenery, and views - given this is surrounded by relatively flat farmland and associated towns for many miles in all directions. A visitor center on the history is a good place to start - takes only 15-20 minutes. Then much of the rest is trails both dirt and boardwalk - overlooking the river, in canyons, or just through rolling terrain in the woods. I'd recommend doing the 80-stair climb to Starved Rock. Then if you handle that fine, you can do a loop where you follow the signs on trails to Wildcat Canyon where you can go down the steps into the canyon - then take the river trail back - which both runs along the river at river level and on bluffs many feet above it with overlooks. We did this "loop" and it took us 2.5 hours for just shy of 3 miles with stops to enjoy, take in the views, and take pictures. But, there are quite a few different options. read more