Three Island Crossing State Park

Three Island Crossing - Glenns Ferry, Idaho

Three Island Crossing was the most important and difficult river crossing in Idaho. Crossing the Snake River was always dangerous, but when the water was low enough to negotiate, everyone crossed who could, to take advantage of the more favorable northern route to Fort Boise. During high water, most emigrants were forced to travel along the South Alternate route into Oregon - a dry, sandy, dusty, and hot trail that wore out man and beast.

On September 11, 1843, William T. Newby ". . . crossed Snake Rive[r]. First we drove over a part of the river one hundred yards wide on to a island, the[n] over a northern branch 75 yards wide on a second island; then we tide a string of wagons together by a chane in the ring of the lead cattles yoak & made fast to the wagon of all a horse & before & him led. We carried as many a[s] fifteen wagons at one time. . . . The water was ten inches up the waggeo[n] beds in the deepe places."

Three Island Crossing State Park maintains a campground, picnic area, interpretive trails, a museum with exhibits, and other visitor services on the north bank of the river.

Three Island Crossing State Park
P. O. Box 609
Glenns Ferry, ID 83623

Map image showing the location for Three Island Crossing.
Map image showing the location for Three Island Crossing.

NPS Image

Last updated: February 12, 2019

Contact the Park

Mailing Address:

National Trails
Oregon National Historic Trail
PO Box 728

Santa Fe, NM 87504


(801) 741-1012

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