The Fortymile River
main stem as well as the North Fork, South Fork, and other tributaries offer a variety of boating possibilities for experienced paddlers of rafts and kayaks, or experienced canoeists willing to
portage around difficult rapids. The many runnable segments vary from Class I (easy) on the
International Scale of River Difficulty to Class V (extremely difficult). In addition to rapids, dangers include overhanging or submerged vegetation and the high probability of confusing one bend in a stream with another—thus entering rapids disoriented and unprepared—without the aid of a map and compass. One of the watershed's hydrologic features,
the Kink, is an artificial channel that is part of a Class V rapids on the North Fork. Mining interests blasted the channel through a ridge in 1904 in order to expose of the original riverbed for prospecting on dry land. The Kink is listed on the
National Register of Historic Places as a significant engineering feat of the early 20th century. ==See also==