Thomas Mitchell Park, just east of Altoona, is ideal for creek walking. There are a few different places you can enter Camp Creek, but our favorite area is near the campground. There's typically parking available near the primitive sites. From there, look for the red bridge and head left until you reach an area with stone steps that lead down to the creek.
I recommend wearing water shoes, Keens work great for both my kids and I. I purchased our shoes on Amazon, but the prices vary wildly so definitely keep an eye out for price drops. I paid $60 for my Keen Women's Whisper Sandals and $40 for my boys' Keen Newport Water Sandals.
I also recommend wearing bug spray if you're walking the creek because there are some overgrown areas. For creek play, we brought along buckets and rubber ducks. My boys had a blast racing their ducks from the bridge to the second set of stone steps.
There are restrooms in the campground shower house and an area to change out of wet clothes or swimsuits. The park also has a hiking trail and playground, which we did during our past visit.