The Yellowstone River is one of our nation’s most remarkable treasures. It’s the last major free-flowing river in the lower 48 states, traveling 680 dam-free miles. The Yellowstone River begins as a melting snowbank on Yount’s Peak deep in the Wyoming wilderness south of Yellowstone Park. From here it runs north then east until it joins the Missouri River in North Dakota.
The upper sections of the Yellowstone River, both inside and outside Yellowstone National Park provide world-famous fly fishing for wild trout. Beginning at the park boundary the river offers 540 miles of unmatched recreational floating. The middle and lower sections of the Yellowstone River remain quite wild. In fact, in some places, it’s nearly the same as when Lewis & Clark explored the West.
The following is an introductory guide to the Yellowstone River which covers the entire 670-mile length of the river.
Yellowstone River Headwaters
The Yellowstone River begins south of Yellowstone Park as snowmelt on Younts Peak in the Teton Wilderness Area. Tiny rivulets merge to form defined creeks which become the South Fork and the North Fork. They join together on the west side of Younts Peak to officially become the Yellowstone River. From there the river runs northward through the Thorofare Region to Yellowstone Park. Although it’s at a fairly high elevation, the terrain here is relatively flat and open. This made it a popular access route for Native Americans and early trappers who named it the Thorofare.
While historically known as an easy route to traverse, today the Thorofare is officially the most remote area in the continental United States. The Thorofare Patrol Cabin in Yellowstone Park is farther from a road than any other building in the lower 48. Built in 1915, the Park Service uses the cabin in the summer and the cabin’s outhouse is a prized destination for hikers. It’s only 32 miles to the most commonly used trailhead!
The Thorofare is remote and wild but it does see visitors. Backpackers and horse pack trips visit the area during the short summer. The section in Wyoming is very popular with big game hunters. To get a great understanding of this special area I recommend the book Hawks Rest: A Season in the Remote Heart of Yellowstone.
Yellowstone Lake
The river enters Yellowstone Park from the south and flows into the Southeast Arm of Yellowstone Lake. Before entering the lake the river meanders through dense stands of willows and is amazing wildlife habitat. Fishing is reported to be excellent but anglers have to be constantly aware of bears. Since the dense willows are more than head-high it can be very unnerving to travel through this area.
Use of the Southeast Arm of Yellowstone Lake is restricted to non-motorized boats. Anyone who wants to visit this area must paddle in or backpack along the shore of Yellowstone Lake. Either of these would be a trip of a lifetime for most.
Yellowstone Lake is a treasure in itself. Sitting at 7,730 ft elevation, it covers 136 square miles and has about 110 miles of shoreline, and is the largest freshwater lake above 7,000 ft in North America. It’s easy to visit as there is a road that follows the lake shore around the north and west sides. The lake is open to boating and commercial tours are available in the summer. They are a great way to experience the lake.
Waterfalls and Canyons
The Yellowstone River drains from the north end of Yellowstone Lake and flows through the majestic Hayden Valley. The meandering river changes character dramatically as it flows over the Upper and Lower Falls into the Grand Canyon of the Yellowstone. This section of the river is wild, remote, and inaccessible. In fact, it’s illegal for visitors to try and descend to the bottom of the canyon. The yellow-colored rock walls of the canyon give the river its name.

The canyon walls gradually lower and the Yellowstone River merges with the Lamar River near Tower Junction in Yellowstone Park. From here it runs through the remote Black Canyon as it heads toward Montana.
Yellowstone River in Montana
Right at the Yellowstone Park boundry, the Yellowstone River is joined by the Gardiner River. This junction, which is right in Gardiner, MT is the furthest upstream point where floaters are allowed to be on the river. From here, the Yellowstone River runs north for 17 miles of mixed flat water and rapids ending in the whitewater rapids of Yankee Jim Canyon. The river continues through the famous “Paradise Valley” until it reaches Livingston, Montana. It’s worth noting that the north-flowing Yellowstone is unusual for major rivers in the US where most flow in a southerly direction.
As it runs through the Livingston area the Yellowstone River makes a gradual sweeping turn to the east and from here the river runs east/northeast for nearly 500 miles across the state of Montana before joining the Missouri River at Fort Union North Dakota. With the recent pattern of low flows and high temperatures some people now consider Livingston to be the border between the upper and middle sections of the river.

For its entire length, the Yellowstone River is unaltered by any major dams making it the longest free-flowing river in the lower 48 states. As a free-flowing river, the Yellowstone experiences an annual flood cycle that results in significant water flow changes over the course of a year. When the snow melts in the spring the river gets high and flooded and as the dry days of summer arrive the river gets low. This is an annual cycle that the river has seen for millennia. Today the fish, animal life, and habitats are much the same as they were when Lewis and Clark visited the area more than 200 years ago.
The 2022 Yellowstone River Flood
As discuessed above, the Yellowstonehas an annual high water period when melting snow fills the rivers and streams. In 2022 massive rain storms hit just as the snow was melting and the ground was saturated. The result wa an unprecedented flood that measure almost twicce as big as anything ever recorded.
The flood did massive damage, the road connecting Mammoth Hot Springs and Gardiner, MT was washed out, buildings and bridges were washed away, the Livingston hosipital was closed, and hundreds of businesses and houses were flooded.
Biologically its too soon to tell if there was much impact but the fish and wildlife should be fine. The river channel has changed quite a bit in places and almost everywhere it has cut a broader stream bottom. It will be interesting to watch over the next few flood cycles to see how and where new pools and channels form.
A Floater’s Paradise
Floating on the Yellowstone River is a cherished activity with lots of opportunities. 540 miles of the river are open to floating, from Gardiner, MT to Fort Union, ND where the Yellowstone joins with the Missouri River. On the Yellowstone, you can find just about any type of water imaginable.

Upper Yellowstone River
Beginning as a whitewater river as it leaves Yellowstone Park, the Yellowstone is a crystal clear and cold trout stream in the upper section. As it flows downstream the river becomes slow, sluggish, and muddy as it reaches its confluence with the Missouri.

The 540 miles of floatable river outside of Yellowstone Park is generally described as having three sections; the upper, middle, and lower. The upper river section is world-famous as a trout fishing mecca. The water in this section is clean, clear, quite cold most of the year, and generally fast flowing. The stretches of the Yellowstone are not formally defined but the upper section is generally considered to be the stretch of river from Yellowstone Park downstream to somewhere around Columbus, Laurel, or Billings, Montana.
Middle Yellowstone River
The middle section of the Yellowstone sees the river transition from a mountain stream to a prairie river. The river becomes larger and gradually slower. The water slowly gets murkier and it’s not as clear as it is in the upper section. Water temperatures are cool but can be very warm in summer. The high temperatures on this section often exceed the lethal tolerance level for trout and far fewer of them are found in this section.

The middle Yellowstone has a diversity of fish species as cold-loving trout species give way to warm water fish such as bass, sauger, and paddlefish. Despite the fact that the river is often paralleled by Interstate 90 and passes through Billings (Montana’s largest city), the middle Yellowstone remains wild. Much of this section is undeveloped and large cottonwood river bottoms with braided channels make chains of islands. Lots of birds and wildlife can be spotted along this section of the river.
Lower Yellowstone River
As the Yellowstone transitions from the middle to the lower sections, it becomes a big slow-moving muddy river. The gradient is low and the rock and cobble bottoms found upstream have gradually been replaced by sand and mud. The fish inhabiting the lower Yellowstone are almost exclusively warm water species yet fishing opportunities can be tremendous.

As with the middle Yellowstone, the lower Yellowstone River has a sprawling river bottom. There are many large wooded islands that are being rapidly invaded by non-native Russian olive and salt cedar. The very lowest part of the river is in oil country. Don’t be surprised to see oil & gas activity on the riverbanks, especially after crossing into North Dakota just before the confluence.
All Boats Must Be Inspected
Beginning in 2019 Montana has instituted mandatory aquatic invasive species inspections on every watercraft that enters from another state. This applies to all boats and not just motorboats. The state operates roadside inspection stations on many highways as they enter the state so watch for signs. This is important and you can face significant penalties if you don’t comply. Information about the Montana Aquatic Invasive Species Program
Camping Along the River
Camping along the Yellowstone is a great way to really experience the river. From Gardiner to Billings you can plan a trip that will allow you to camp at public sites. However, there are a few opportunities for setting up camp in undeveloped places along the river. Almost all of the lands along the river are privately owned and it is never OK to camp on private land without permission. Some of the fishing access sites on the river that allow camping include Carbella BLM River Access, Dan Bailey Access, Loch Leven Access and Mallard’s Rest.
That said, there are camping opportunities that you can pursue. In Montana, everything between high water marks is considered public land and is open to float camping. The state rule says camping is not allowed unless “it is necessary for the enjoyment of the surface water and the campsite is not within sight of any occupied dwelling or the campsite is more than 500 yards from any occupied dwelling, whichever is less;” On the Yellowstone, there are many small islands and gravel bars that fall into this classification and with a bit of care you can usually find a site. Make sure you understand all of the rules pertaining tot he stream access law. MFWP has produced this Montana Stream Access Law brochure.

You can never count on finding a good camping site on demand. Consequently, I recommend you begin looking for a good site early and, if you find a good spot, go ahead and make camp. It’s no fun being on the river as it’s getting dark and all you can find is posted private property. I’ve been forced to spend the night on my boat because of not setting up camp early.
Yellowstone River Fishing
There are great fishing opportunities along the entire Yellowstone. With everything from clear icy mountain streams to slow, warm, muddy waters there is fishing for almost every angler.
Fly fishing rules on the upper stretch of the river. Beginning at Gardiner, the Yellowstone is famous for its excellent trout fishing. While almost everyone fishes with flies, some prefer artificial lures or even bait. If you plan to keep fish to eat you must be very careful. It’s catch-and-release fishing only for cutthroat trout and there are special regulations on some sections. Always check the regulations!
The Yellowstone gradually slows and warms as it moves east from Livingston. Smallmouth bass begin to be captured and ling fishing is very popular with some anglers. This is still suitable habitat for trout and they remain the main target. As the river continues on the trout become more isolated but they are still caught, even to the east of Billings. There are never distinct boundary lines for fish and gradually sauger, catfish, and many other fish are eagerly sought.
As the fish species mix changes so too do angling methods. While fly fishing dominates the upper river, artificial lures and live bait become the norm. Also, the upper river is almost completely non-motorized floating but becomes widely used by powerboats.
Fishing for Paddlefish – Living Dinosaurs
One of the most unusual fishing opportunities in North America is the annual paddlefish season at the Intake dam near Glendive, MT. Paddlefish are ancient creatures that are little changed from the days of dinosaurs. They are very long-lived – up to 60 years and the largest recorded in Montana was 142 pounds. However, it is unusual to catch one over 100 pounds. They are closely related to sturgeon and, like them, produce massive amounts of eggs that are prized for caviar. There is actually commercial caviar produced in Montana from paddlefish eggs.
Anyone who wants to can fish for paddlefish but there are limits on how many can be harvested each year. Paddlefish swim upstream to spawn every spring and they concentrate in the waters below the Intake irrigation dam. Here, anglers line up to try and catch them by snagging. They cast out heavy treble hooks and bring them back in long pulls hoping to snag into a giant fish. There is a limit of one fish per person per year and the total harvest is limited. If you want to catch one plan to be there when the season opens as they can quickly reach the quota in a good year.
Learn more in this video:
Every inch of the Yellowstone River is amazing and you will be rewarded if you explore any part. There are a number of excellent books about the Yellowstone River. I particularly recommend:
Montana’s Yellowstone River: From the Teton Wilderness to the Missouri
Downriver A Yellowstone Journey
Fly Fishing the Yellowstone River: An Angler’s Guide