🌤 Weather at Glenns Ferry Historical State Park by season
| Spring | Summer | Fall | Winter |
|---|---|---|---|
| 32–78 °F | 53–99 °F | 29–86 °F | 24–50 °F |
Each range runs from the coldest monthly average low to the warmest monthly average high in that season (1991-2020 climate normals), measured at Glenns Ferry, 0 mi away, elevation 2,466 ft. Conditions at the park can differ from the station, especially where elevation differs — check a forecast before you go.
Historic Oregon Trail River Crossing on the Snake River in Idaho — State Park Preserving the Most Dangerous Crossing Point on the Entire Oregon Trail, Where Thousands of Emigrant Wagons Forded the Snake River at Three Island Crossing, Oregon Trail History Center With Interpretive Exhibits and Living History, Annual Three Island Crossing Re-Enactment in August, Campground With Full Hookups on the Snake River, Fishing and Swimming in the Snake River, Hiking Trails Through Desert Landscape and Along the Historic Trail Route, Near Glenns Ferry Elmore County Southern Idaho Snake River Plain
Three Island Crossing State Park (also known as Glenns Ferry Historical State Park) is a state park in Glenns Ferry, Elmore County, southern Idaho, managed by Idaho Department of Parks and Recreation. The park preserves the most critical and dangerous river crossing on the entire Oregon Trail, featuring the historic Three Island Crossing where thousands of emigrant wagons forded the Snake River — those who crossed successfully followed a better route to Oregon while those who failed were often swept away, an Oregon Trail History Center with interpretive exhibits documenting the crossing and the broader emigrant experience, the annual Three Island Crossing Re-Enactment in August — a dramatic recreation of the actual wagon and livestock river crossing, a campground with full hookups on the banks of the Snake River, fishing and swimming in the Snake River, hiking trails through high-desert sagebrush landscape and along the historic trail route, and visible trail ruts and emigrant artifacts preserved in the landscape.
The crossing decision was life-or-death — emigrants who successfully forded the Snake River here gained access to a better, greener route to Oregon with more water and grass. Those who couldn’t or wouldn’t cross were forced onto the brutal South Alternate Route through waterless desert.
The August re-enactment brings this history to life — horses, wagons, and livestock actually cross the Snake River at the historic fording point, giving spectators a visceral understanding of the danger and determination that defined the Oregon Trail experience.
Things to Do
- Oregon Trail crossing — historic site
- History Center — exhibits, artifacts
- Re-enactment — August crossing
- Camping — full hookups, Snake River
- Fishing — Snake River
- Trail ruts — visible in landscape
Park Information
| Feature | Details |
|---|---|
| Location | Glenns Ferry, Elmore County, ID |
| Trail | Oregon Trail — Three Island Crossing |
| Event | August re-enactment |
| Camping | Full hookups on Snake River |
| Fishing | Snake River |
| Managed By | Idaho Dept. Parks & Recreation |
| Coordinates | 42.9500° N, 115.3000° W |
Wildlife & Nature
Glenns Ferry HSP — at the Three Island Crossing — the most famous Snake River crossing on the Oregon Trail. The park’s Snake River, desert, and islands support white sturgeon (prehistoric fish), bald eagles, and mule deer.
Nearby Attractions
Glenns Ferry — adjacent. Snake River — at the park. Elmore County — surrounding.
What is Three Island Crossing on the Oregon Trail?
Three Island Crossing in Glenns Ferry, Idaho was the most critical and dangerous river crossing on the entire Oregon Trail — emigrants who successfully forded the Snake River gained access to a better route to Oregon. Today, Three Island Crossing State Park preserves the historic site with an Oregon Trail History Center, annual August re-enactment with actual river crossings, camping with full hookups on the Snake River, and visible trail ruts. Managed by Idaho Parks and Recreation.
Last updated: May 2026
More parks nearby: Three Island Crossing State Park is a short drive away, while Bruneau Dunes State Park lies within about an hour’s drive.
🐾 Dogs & Pets at Glenns Ferry Historical State Park
- Pets allowed? statewide rule
- Pets are welcome in most Idaho state parks and on trails, but only if confined or controlled on a leash no longer than 6 feet.
- Leash rule statewide rule
- 6 ft maximum leash required, or pet must be confined (e.g. in a camper)
- Beaches & swim areas statewide rule
- Pets are prohibited from all swim areas and beaches statewide (service animals excepted)
- Cabins & lodging statewide rule
- Pets are allowed at most parks but some parks prohibit them in some cabins and yurts
- Statewide exceptions statewide rule
- Park managers may designate off-leash exercise areas (e.g. Eagle Island off-leash trails); pets may not be left unattended
Are dogs allowed at Glenns Ferry Historical State Park?
Pets are welcome in most Idaho state parks and on trails, but only if confined or controlled on a leash no longer than 6 feet. Individual parks can post stricter rules — check signage on arrival.
Rules verified July 2026 via parksandrecreation.idaho.gov. More: Idaho state parks guide · Dog rules in all 50 states compared
Park Location
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