Yellowstone River Trail
Length to Gardiner, Montana from: 
Hellroaring Gravel Pit Trailhead 16.75 miles, one way.  
Hellroaring Ford 14.75 miles, one way. 
Cottonwood Creek 11.1 miles, one way. 
Blacktail Bridge 7.75 miles, one way. 
Crevice Creek Bridge 6.7 miles, one way. 
Bear Creek Bridge 1.75 miles, one way.  
Elevation change: Blacktail/Gravel Pit Trailhead at 6,520 feet (1,252-foot loss).
Trailhead: The trailhead begins at the Hellroaring/Gravel Pit parking area, 3.4 miles west of Tower Junction on the Mammoth-Tower Road, just beyond Floating Island Lake.

The Yellowstone River Trail is one of the longest trails in the northern section of the park, and most hikers who take on this trail do so as a two-day trip. It also has the distinction of having the lowest elevation of any trail in the park. For this reason, it can be hiked early in the season when most trails are still buried under snow. The only drawback of an early spring hike is the spring runoff. Many of the Yellowstone River's tributaries, including the river itself, usually are swollen and treacherous to cross or ford. Several creeks along this stretch, including Hellroaring, Little Cottonwood, Cotton-wood, Crevice (footbridge) and Bear (footbridge), can be very dangerous. At Hellroaring, the beginning of the Yellowstone River Trail, a crossing is provided 0.8 miles upstream. The bridge adds a few extra miles, but safety is a factor.

The Yellowstone River Trail is accessed by the Hellroaring/ Gravel Pit Trailhead. The Hellroaring Creek Trail (see Hellroaring Creek Trail for description) leads to Hellroaring Ford and the beginning of this trail. After either fording the stream (only late in the season when the water level is down and it is safe to cross) or by using the bridge upstream, the Yellowstone River Trail begins its descent along the river to Gardiner, Montana.

The flora and fauna is entirely different along this trail than it is along the higher trails in the interior of the park. A few large Douglas fir trees are common, but most are Rocky Mountain junipers. In late July or August, check the trunks of these trees for shells or skins of cicadas. These large insects spent most of their lives as grubs underground, feeding on the roots of the tree. They then emerge and begin their metamorphosis into membranous winged adults. During the summer, you will hear their shrill droning sound, which is produced by specialized organs.

This area also is a refuge for wintering big-game animals, including mule deer, elk, bighorn sheep and predators such as the mountain lion and coyote. Even during the summer, there are telltale signs of their presence. Droppings, patches of shed winter coat, dropped antlers and overgrazed vegetation all are signs of their stay.

Most of the valley forms a tight gorge with fairly steep walls beginning at Cottonwood Creek. This is known as the Black Canyon because of the darkness produced by the close canyon walls. Cottonwood Creek is a popular campsite and a good first-day hike. Little Cottonwood Creek also is a good campsite, with a spring nearby. But use a water filter before drinking any water, and make sure you have plenty of good drinking water for this journey.

The Blacktail Deer Creek Trail (see Blacktail Deer Creek River Trail,for description) joins the Yellowstone River Trail at the suspension bridge and at the 9.0-mile marker. The river can be exited from this point, but it is a 1,078-foot, 3.4-mile climb to the Blacktail Trailhead.

The next landmarks are Crevice Creek and just beyond Knowles Falls, at the 10.75-mile mark. Do not expect another Lower Falls. The river is constricted through rock formations and only produces a 15-foot plunge. Even so, the force and power is impressive. From Knowles Falls, the landscape becomes even more desert-like, and the possibility of seeing snakes increases. Bull and garter snakes are common, and it is possible-though not highly probable-to find a rattlesnake, so take precaution when hiking this trail. The trail emerges at Gardiner, just north of the Yellow-stone Bridge in the downtown area.

Lost Lake-Petrified Tree Trail
Length: 3.1 miles, loop via Lost Lake and Petrified Tree. 
Length from Roosevelt Lodge to:
Lost Creek Falls (spur trail) 0.25 miles
Lost Lake 0.8 miles
Petrified Tree 1.8 miles
Tower Ranger Station (via Petrified Tree) 2.7 miles
Elevation change: Trailhead at 6,340 (460-foot gain). 
Trailhead: The trail starts behind Roosevelt Lodge. Or, as an alternate route, start at the Petrified Tree, about a quarter mile east of the Blacktail Plateau Drive exit or about 1.4 miles west of Tower Junction.

The trail begins directly behind Roosevelt Lodge. It crosses a footbridge and over a wet seep shrouded with ferns. From there a short spur trail leads to Lost Creek Falls, a 40-foot plunge into a steep, dark, timber-covered canyon. From the junction to Lost Creek Falls, the trail climbs south up a steep 350-foot rocky rim. On the bench above the rim, the trail then joins the horse trail and continues west to Lost Lake and Petrified Tree. The trail east heads to Roosevelt Corral and approximately 2.5 miles to Tower Campground (see Roosevelt-Tower Trail for description).

In 1975, an earthquake with an epicenter near Norris Geyser Basin shook the Yellowstone region. It brought down delicate spires in the Grand Canyon, and along this rim, large rockfalls tumbled down the canyon, nearly striking passing hikers.

The trail continues along the shore of Lost Lake, where beaver activity usually can be spotted. In late June through early July, the edges of this lake are covered with the arrow-shaped, leather-like leaves and yellow, baseball-sized flowers of yellow pond lilies. The trail follows the drainage of Lost Lake through Douglas fir and aspen, and emerges at the Petrified Tree parking area.

The Petrified Tree has a substantial iron fence that was installed in 1907 for its protection. At one time, there were several trees in the vicinity, with broken remnants scattered on the hillside, but collection and souvenir hunters removed these piece by piece, including a whole fossilized tree. The remaining tree is a siliceous replica-a fossil-of an ancient redwood. To continue back to Roosevelt Lodge, the trail climbs the hill at the northeast end of the parking area. (For winter skiing, the short spur road to Petrified Tree is unplowed, and access to this trail and parking is at the turnout on the Mammoth-Tower Road.) From the parking area, this trail leads over the saddle between two hills and behind the Tower Ranger Station and through the Park Service employee-housing area to the cabins at Roosevelt Lodge. The trail emerges at Hamilton General Store.

Yellowstone River Picnic Area Trail
Length from Yellowstone River picnic area to: 
Calcite Springs View 1.0 miles, one way. 
Four-way junction 2.0 miles, one way.
Bannock Ford (spur trail) 2.4 miles, one way. Return to picnic area 4.0-mile loop. Elevation change: Trailhead at 6,200 feet (414-foot gain to The Narrows viewing area). 
Trailhead: Located at the Yellowstone River picnic area, a mile north of Tower Junction on the Northeast Entrance Road.

This trail is a short easy hike and provides wonderful views of Calcite Springs, the narrows of the Yellowstone, the Overhanging Cliff, the towers of Tower Falls, the basalt columns and the historic Bannock Indian Ford. It also offers views of the Tower General Store and the Tower-Canyon Road, and provides access to the Specimen Ridge Trail (see Specimen Ridge Trail for description) above the Bannock Ford. From the picnic area, the trail heads south and parallels the Yellowstone River. The trail runs very close along the river canyon, and drop offs are common near the trail. Take precautions while hiking this stretch of the trail.

Bighorn sheep occasionally are spotted in this area during early spring and fall, as they migrate to and from the high country in the Washburn area. The primary trees along the rim are Douglas fir, limber pine and Rocky Mountain juniper.

The trail meets a four-way junction, the southern trail leads to the Bannock Indian Ford. The eastern trail leads to Specimen Ridge, a long, hot and grueling hike to the petrified forest. The northern trail leads directly to the Northeast Entrance Road and emerges at the glacier exhibit turnout. This is the continuing trail for the loop hike, but it is not highly recommended because the return route follows the road for the last mile. The recommended route is to return on the same trail from the four-way junction. The Bannock Indian Trail, branching south at the four-way junction, descends steeply to the bottom of the Grand Canyon at Tower Falls. The Great Bannock Trail crosses the Yellowstone at the point of a small island. Indians used this ford during their migrations until the 1870s, at which time early trappers and explorers began to use it. John Colter also is credited with using the ford during his historic 1807-1808 winter trip through Yellowstone, even though his exact route has never been known.

The trail meets a four-way junction, the southern trail leads to the Bannock Indian Ford. The eastern trail leads to Specimen Ridge, a long, hot and grueling hike to the petrified forest. The northern trail leads directly to the Northeast Entrance Road and emerges at the glacier exhibit turnout. This is the continuing trail for the loop hike, but it is not highly recommended because the return route follows the road for the last mile. The recommended route is to return on the same trail from the four-way junction.

The Bannock Indian Trail, branching south at the four-way junction, descends steeply to the bottom of the Grand Canyon at Tower Falls. The Great Bannock Trail crosses the Yellowstone at the point of a small island. Indians used this ford during their migrations until the 1870s, at which time early trappers and explorers began to use it. John Colter also is credited with using the ford during his historic 1807-1808 winter trip through Yellowstone, even though his exact route has never been known.

Trout Lake
Length: 0.5 miles, one way.
Elevation change: Trailhead at 6,800 feet (ISO-foot gain). 
Trailhead: The trailhead is located on the west side of the Northeast Entrance highway, about 1.3 miles south of Pebble Creek Campground or 17.5 miles northeast of Tower Junction, The trailhead is unmarked, but there is a vehicle turnout.

Trout Lake is known for its excellent fishing, but also is a great short hike. The trail begins from the turnout and immediately begins a steep climb, with switchbacks, over a small ridge covered with Douglas fir and lodgepole pine. At the top of the ridge is a large Douglas fir and the first view of Trout Lake. At the outlet is an eight- to nine-foot dam constructed between 1919 and 1950 when Trout Lake, then known as Fish Lake, operated as a fish hatchery. Originally, cutthroat trout were spawned here but, by 1934, rainbow trout were planted to provide eggs for other park lakes. By the early 1940s, rainbow-cutthroat hybrids were discovered, and the lake was opened for fishing in 1994. The lake water is clear and only 17 feet at its deepest, but dense aquatic vegetation grows around the edge, making it difficult to catch the large trout that abound here. Ducks also prefer this shallow lake, rich in aquatic food. A perimeter trail crosses the outlet and also leads to Buck and Shrimp lakes which contain few, if any, fish. From Trout Lake are great views of The Thunderer (10,554 feet) to the east, past open meadows to Mt. Hornaday (10,036 feet) to the north and Druid Peak (9,583 feet) to the west, just beyond the immediate rocky cliff.