Whistle Trail is named for the low-water bridge that connects the main park to the picnic area. The bridge is so named because of the large tubes that resemble whistles through which the stream water flows. The trail runs along the stream branch most of the time, but allows access to some bluff tops as well.
At the south end, the trail overlaps with Forrest Trail. Whistle Trail divides at the south end of the bluffs, with one side of the trail traveling along the top of the bluff and the other along the base and next to the water. After these two trails reconnect at the north, the trail ascends a steep bluff and then gradually descends toward the picnic area to the north of Whistle Bridge. A short travel through the parking area of the picnic area leads to the continuation of the trail. Traveling north on this section leads through a bottomland area and then hugs the bottom of steep hillsides until connecting at the north end with a parking area near the Niangua River. A bridge at the north end allows for an alternative loop that returns on the linear trail. Several areas along the trail offer good overlooks to the valley.
Much of the tread is narrow, rocky and can be slippery when wet. The trail ascending and descending the bluffs can be treacherous under wet conditions. Only daytime activities are now allowed in the area. Portions of the trail are inaccessible during high water. The length of the trail is one mile with an estimated hiking time of 45 minutes one way. The north trailhead is is off of Bramwell entrance road at the bottom of the hill.