A roughly 24-mile freestone tributary of the East River, dropping out of the Elk Mountains and running past the town of Crested Butte before joining the East southeast of town.
The Slate is the smaller of the valley's freestone pair — town water for Crested Butte, sliding right past it on the way down from the Elk Mountains. Like the East it lives on snowmelt, running high through late spring and coming into shape as runoff recedes, and like most of the valley it interleaves public reaches with private land. Confirm access for the stretch you have in mind before you go.
The Slate River is canonically tracked, but Ghost Town holds no fishing reports for it yet. Ask Ghost Town and it will say exactly that — while showing what it holds for the valley's other rivers.
Ask Ghost Town about the Slate →Gunnison Valley fly shops and guide services in Ghost Town's source directory report on the valley's waters; Slate coverage grows as those sources publish.
USGS operates a gauge on the Slate near Crested Butte, but Ghost Town has not yet linked it — so this page shows no number rather than an unverified one.
A Colorado fishing license is required, sold by Colorado Parks & Wildlife. Private land borders sections of the Slate and seasonal wildlife closures can apply in the upper valley — confirm current rules and access with CPW before you fish.
Ask what Ghost Town knows for your dates — it holds current reports for the Gunnison and Taylor, and it will tell you honestly where the Slate's coverage stands.
Ask Ghost Town about the Slate River