Hell Roaring Creek is a tributary of the Red Rock River. Greg Slayden over at county highpointers wrote a nice piece abut visiting the site.
While we're on the topic, Lake Itasca offers all sorts of fun speculation. John Brower who i.d.'d Brower's Spring has his reputation based on declaring that the north arm of the lake is the source of the Mississippi. But then there are a whole bunch of streams/ponds and higher elevation points to the south that by the same logic should be the starting point of the Mississippi.