I'm sorry, but there is an error in your question. Cascade River State Park is actually located in Minnesota, not Illinois. Here's a summary about the park in Minnesota:
Cascade River State Park is a popular destination for nature lovers in Minnesota. The park is situated on the north shore of Lake Superior, and it features a beautiful, cascading river and numerous hiking trails. Visitors can also go fishing, birdwatching, and camping. Some of the specific points of interest to see include the Cascade Falls, which is a 30-foot waterfall, and the Superior Hiking Trail, a 310-mile trail that runs through the park. Interesting facts about the area include that it was once home to the Ojibwe people and was also a logging site in the late 1800s. The best time of year to visit is during the summer months when the weather is mild and the trails are accessible. However, the fall season is also a popular time to visit for the fall colors.