the Oregon Trail had been established, generally following much of the Snake River. One crossing the trail made over the Snake River was near the present-day site of Glenns Ferry. Several years later, a ferry was established at the site, replacing the old system where pioneers had to ford the wide, powerful and deep Snake. Another place where pioneers crossed the Snake was further upstream, at a place called "Three Island Crossing", near the mouth of the Boise River. This area has a group of three islands (hence the name) that splits the Snake into four channels each about wide. Some emigrants chose to ford the Snake and proceed down the west side and recross the river near Fort Boise into Hells Canyon, continue down the drier east side into the gorge, or float the Snake and Columbia to the Willamette River, the destination of the Oregon Trail. The reason for the Three Island Crossing was the better availability of grass and water access. Numerous ferries have provided crossings of the upper Snake from the Brownlee Ferry at the head of Hell's Canyon to Menor's Ferry, which operates today at Moose, Wyoming. Sophistication varied from reed boats pulled by Indians on horse back at Snake Fort, Fort Boise, as described by Narcissa Whitman in 1836 to an electric operated ferry, the Swan Falls Ferry, at Swan Falls Dam of the early 20th century. One contemporary diarist crossing near Salmon Falls complains of "exorbitant" fees at the crossings that were a "constant drain" on the traveler's purse. She writes that this particular route was controlled by Mormons who had "built bridges where they were not needed-most unmercifully fleecing the poor emigrants". The diarist expresses regret at having made the crossing describing the landscape as "desolate country". Another writer similarly notes several days travel through "a desert so desolate and rocky that we almost regretted that we had not continued on the south side of that stream". Steamboats Unlike the Columbia River, it was far more difficult for steamboats to navigate on the Snake. The Columbia River drops from source to mouth, while the Snake drops over in elevation over a length more than shorter. Still, from the 1860s to the 1940s, steamboats traveled on the Snake River from its mouth at the Columbia River to near the mouth of the Imnaha River in lower Hells Canyon. However, most of the steamboats