Twin Falls State Park

To get there, head east on I-90 to exit 34, turn right and follow the little brown information signs to the state park. This trail has several ups and downs to several great view points. The hike is very pleasant with the sounds and sights of the river and its rapids. At the top of the first up section, one gets the first views to the falls. Then down and up to a trail junction. Take the right fork down to an incredible view of the lower falls. Return to the main trail, continue up, and cross a bridge with more great views. Continue up to one more view point of the upper falls. From here the trail continues up but I have trouble recommending it. There are 2 unpleasant blow downs to navigate around plus the sights and sounds of I-90 are somewhat annoying. The trail does connect with the old railroad grade so a one-way option is to start at the parking lot at exit 38 and Olallie State Park.