Thielsen Creek Trail has a total elevation difference of 1,730 feet, and that is about average. Thielsen Creek Trail is 9.2 miles long; it's longer than many wilderness hiking trails. This walk shouldn't take more than 8 hours, but you never know stuff could go wrong and you could get stuck so be prepared for that. Some parts of this wilderness hiking trail are much higher up than other parts of the wilderness hiking trail, so keep in mind that you may need to dress differently at different elevations. There is only one trailhead, so you'll be backcountry backpacking it in and back out. This backpacking and hiking trail sometimes gets very dry, so do check for current fire restrictions before you go if you plan to bring a stove or make a camp fire. Now this backpacking and hiking trail is pretty long, so do pack enough food to last the whole trip.