Dull Knife Reservoir is a 130-acre public trout fishery on Hazelton Road (Johnson County Road 3), about 11 miles south of US-16 on the southern end of the Bighorn Mountains. It holds rainbow, brown, and cutthroat trout, with year-round foot access but no camping or services on-site. It's about 12 minutes from Piton, the closest Wyo Stays cabin to the reservoir.
Dull Knife Reservoir: A Fishing Guide from the Bighorn Side
130 acres of trout water on a county road most visitors never turn down.
Dalton Goodyear · August 2026 · 6 min read
Most fishing guides to the Bighorn Mountains point you toward the Tongue River or the alpine lakes near the Medicine Wheel Passage on the eastern side of the range. Dull Knife Reservoir sits on the other side — the southern Bighorns, down Hazelton Road off US-16, on the Buffalo–Ten Sleep corridor most visitors drive through rather than stop in.
The Basics
Dull Knife Reservoir is a 130-acre public access area managed by the Wyoming Game and Fish Department, sitting roughly 11 miles down Hazelton Road (Johnson County Road 3) from where it branches off US-16. Access is foot-only from the parking area, and it's open year-round for fishing, though winter conditions on the approach road can complicate a cold-season trip.
The reservoir holds rainbow, brown, and cutthroat trout — a genuine mixed fishery rather than a single-species put-and-take pond. There are no services and no camping at the reservoir itself; it's built for a day trip, not a basecamp.
A 130-acre trout fishery most Bighorn visitors never hear about, because it's not on the way to anywhere else.
Getting There
From US-16, turn onto Hazelton Road (Johnson County Road 3) and follow it roughly 11 miles to the reservoir's access area. This is the same road that leads to Piton, the Wyo Stays cabin in the southern Bighorns — the reservoir and the cabin sit close enough together that a fishing trip and a cabin stay pair naturally.
Cell coverage along Hazelton Road is unreliable, so download directions before you leave US-16 in either direction. The road itself is a mix of paved and gravel sections typical of Bighorn National Forest access roads — check current conditions before a shoulder-season or winter trip.
Day Use Only
There is no camping or services at Dull Knife Reservoir. Pack out what you pack in, and plan your overnight stay elsewhere — Piton, about 12 minutes away on the same road, is the closest option.
Planning the Trip
Foot access from the parking area means this isn't a drive-to-the-shoreline stop — bring gear appropriate for a walk-in day of fishing. Early morning and evening are generally the better windows for trout activity at this elevation, and the southern Bighorns' relative obscurity compared to the range's eastern side means you're less likely to be sharing the water with a crowd.
A trip here pairs naturally with a stay at Piton — close enough for an easy morning or evening outing without eating into a full day, and a real kitchen back at the cabin for whatever you bring home.
Fish Dull Knife, Stay at Piton
12 minutes down the same road, sleeps 12, a wood stove for the evening after.
View PitonWyo Stays · Licensed Wyoming Real Estate Brokerage · (307) 312-9656
Frequently Asked Questions
Rainbow, brown, and cutthroat trout, per Wyoming Game and Fish Department data. It's managed as a public trout fishery on the southern end of the Bighorn Mountains.
No — there are no services or camping available at the reservoir itself. It's a day-use fishing access area. Campers should look to other Bighorn National Forest campgrounds or Johnson County options.
Via Hazelton Road (Johnson County Road 3), which branches off US-16 south of the highway. The reservoir sits roughly 11 miles down Hazelton Road from US-16, on the southern end of the Bighorn Mountains.
Foot access is available year-round according to Wyoming Game and Fish, though winter conditions on Hazelton Road itself can restrict vehicle access. Check current road conditions before a cold-season trip.
About 12 minutes — Piton and the reservoir are both on the Hazelton Road corridor in the southern Bighorns, making it one of the closest named attractions to the cabin.