The Lamar's total course is over forty miles, but there are only about eight miles of it that are accessible from a road.
You can follow it to its confluence with the Yellowstone River along the Northeast Entrance Road.
At a glance, it appears an average freestone fly fishing stream.
Any angler who's cast a fly over the Lamar River will tell you a different story.
Tips on fly fishing the Lamar River in Yellowstone National Park from Sweetwater Fly Shop
Due to the difficulty accessing the river, all but the first few miles of the Lower Lamar River rarely see much fishing.
Those anglers wishing to try their luck further upstream must hike their way into the backcountry or take the trail on horseback. The tricky part is negotiating the steep decline through a canyon to gain the uppermost reaches of the Lamar.
The trout are not as large on the Upper Lamar as they are along the Lower Lamar, but the action here is much faster than downstream. The prized westslope cutthroat trout are smaller here but far more plentiful than other parts of the river, and some measure more than 18 inches.
The best part of fishing the Lamar River isn't just the trout: the Lamar Valley is among the most beautiful vistas in Yellowstone National Park. It is a massive stretch of a landscape teeming with every type of life.
Sightings of wolves, elk, and even grizzly are relatively common here, and you couldn't ask for a more stunning backdrop that represents the best of the American West.
Of course, there are rainbows, brook, brown, and cutthroat trout ripe for the catching, but the setting somehow makes it all seem so much more worth the effort and the long hike.
Click the map icons to get directions to fishing spots, boat ramps and real-time USGS stream flow data
Determining your fishing spot largely depends on how far you are willing to hike or ride into the backcountry. If you want to fish the headwaters, you are in for a 30 mile trip into some serious wilderness territory.
For the less adventurous, road access begins around Soda Butte Creek (an excellent fishing stream in its own right). The Lamar River flattens out a bit here, and the trout tend to be larger, too. The fish here seldom see an angler, so it's a good place if you are looking for easy pickings.
For a real challenge, move further down the river into the Lamar Valley. The river continues to flatten out here with fast short rifles punctuating long glides and runs of clear freestone.
The Lamar Valley is a place for genuinely skilled anglers, and your fly, leader, and presentation techniques must be near flawless. The trout here are far more cunning, and they won't strike at just any meal that appears to come their way.
Know the hatches and patterns here for the season you visit, and bring your A game: the local trout are fierce fighters.
The fishing season for Yellowstone National Park only runs Memorial Day Weekend to the first Sunday in November. The short season is primarily because most of Yellowstone is inaccessible once the winter snowfall begins.
As far as the Lamar River is concerned, the most significant hatches of the year are in July and August, and it is the best possible time to visit Lower or Upper Lamar River for some fast and furious fly fishing action.
Tourist season tends to slow a bit after July as well, so you also will have to contend with fewer tourists on the road and booking local accommodations as well.
Pack your rain gear in case you get caught in a summer thunderstorm on the Upper Lamar River, and a pair of breathable waders are a must have if you want to get the most out of your trip to the Lamar.
A 9-foot 5-wt fly rod with floating line is perfect for fishing dry flies and small nymphs on the Lamar River. For larger nymphs and streamers a 9-foot 6-wt makes life a little easier. A tapered 9-foot leader, with tippet size 3X to 6X to match the flies you are throwing, is pretty standard.
Hatches on the Lamar River include:
- BWOs shortly after spring runoff, in July, and September
- PMDs after runoff through August
- Spotted sedge, green sedge, and little short-horned sedge caddisflies, July-August
- Gray Drakes, July-September
- Terrestrials July-September
There are a number of area fly shops and on-line retailers that can provide Lamar River fishing reports. A few to check out are listed below.
Fly into Bozeman and take some time to walk around downtown. There are many traditional hotel and motel accommodations to be had here, and the city itself has a unique charm. There are several world-class outfitters in town too should you need gear and advice.
There are also local ranches and bed and breakfasts where you can stay in between forays south into Yellowstone if you prefer accommodation with more local character.
If you prefer to stay in the park, there are several lodges to choose from, or you can camp if that's to your taste. Don't forget to check out locally listed vacation rentals as well. It's an easy way to score a bargain on your stay.
Looking for more places to fish? Visit our DIY Guide to the Best Fly Fishing in Yellowstone National Park.
Ken is an avid fisherman of 40+ years who loves to explore and find new places to fish. He created DIY Fly Fishing to help you do the same.
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